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2388 jpm 1
<?php
2
/**
3
 * PHPExcel
4
 *
5
 * Copyright (c) 2006 - 2013 PHPExcel
6
 *
7
 * This library is free software; you can redistribute it and/or
8
 * modify it under the terms of the GNU Lesser General Public
9
 * License as published by the Free Software Foundation; either
10
 * version 2.1 of the License, or (at your option) any later version.
11
 *
12
 * This library is distributed in the hope that it will be useful,
13
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15
 * Lesser General Public License for more details.
16
 *
17
 * You should have received a copy of the GNU Lesser General Public
18
 * License along with this library; if not, write to the Free Software
19
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20
 *
21
 * @category	PHPExcel
22
 * @package		PHPExcel_Calculation
23
 * @copyright	Copyright (c) 2006 - 2013 PHPExcel (http://www.codeplex.com/PHPExcel)
24
 * @license		http://www.gnu.org/licenses/old-licenses/lgpl-2.1.txt	LGPL
25
 * @version		##VERSION##, ##DATE##
26
 */
27
 
28
 
29
/** PHPExcel root directory */
30
if (!defined('PHPEXCEL_ROOT')) {
31
	/**
32
	 * @ignore
33
	 */
34
	define('PHPEXCEL_ROOT', dirname(__FILE__) . '/../../');
35
	require(PHPEXCEL_ROOT . 'PHPExcel/Autoloader.php');
36
}
37
 
38
 
39
require_once PHPEXCEL_ROOT . 'PHPExcel/Shared/trend/trendClass.php';
40
 
41
 
42
/** LOG_GAMMA_X_MAX_VALUE */
43
define('LOG_GAMMA_X_MAX_VALUE', 2.55e305);
44
 
45
/** XMININ */
46
define('XMININ', 2.23e-308);
47
 
48
/** EPS */
49
define('EPS', 2.22e-16);
50
 
51
/** SQRT2PI */
52
define('SQRT2PI', 2.5066282746310005024157652848110452530069867406099);
53
 
54
 
55
/**
56
 * PHPExcel_Calculation_Statistical
57
 *
58
 * @category	PHPExcel
59
 * @package		PHPExcel_Calculation
60
 * @copyright	Copyright (c) 2006 - 2013 PHPExcel (http://www.codeplex.com/PHPExcel)
61
 */
62
class PHPExcel_Calculation_Statistical {
63
 
64
 
65
	private static function _checkTrendArrays(&$array1,&$array2) {
66
		if (!is_array($array1)) { $array1 = array($array1); }
67
		if (!is_array($array2)) { $array2 = array($array2); }
68
 
69
		$array1 = PHPExcel_Calculation_Functions::flattenArray($array1);
70
		$array2 = PHPExcel_Calculation_Functions::flattenArray($array2);
71
		foreach($array1 as $key => $value) {
72
			if ((is_bool($value)) || (is_string($value)) || (is_null($value))) {
73
				unset($array1[$key]);
74
				unset($array2[$key]);
75
			}
76
		}
77
		foreach($array2 as $key => $value) {
78
			if ((is_bool($value)) || (is_string($value)) || (is_null($value))) {
79
				unset($array1[$key]);
80
				unset($array2[$key]);
81
			}
82
		}
83
		$array1 = array_merge($array1);
84
		$array2 = array_merge($array2);
85
 
86
		return True;
87
	}	//	function _checkTrendArrays()
88
 
89
 
90
	/**
91
	 * Beta function.
92
	 *
93
	 * @author Jaco van Kooten
94
	 *
95
	 * @param p require p>0
96
	 * @param q require q>0
97
	 * @return 0 if p<=0, q<=0 or p+q>2.55E305 to avoid errors and over/underflow
98
	 */
99
	private static function _beta($p, $q) {
100
		if ($p <= 0.0 || $q <= 0.0 || ($p + $q) > LOG_GAMMA_X_MAX_VALUE) {
101
			return 0.0;
102
		} else {
103
			return exp(self::_logBeta($p, $q));
104
		}
105
	}	//	function _beta()
106
 
107
 
108
	/**
109
	 * Incomplete beta function
110
	 *
111
	 * @author Jaco van Kooten
112
	 * @author Paul Meagher
113
	 *
114
	 * The computation is based on formulas from Numerical Recipes, Chapter 6.4 (W.H. Press et al, 1992).
115
	 * @param x require 0<=x<=1
116
	 * @param p require p>0
117
	 * @param q require q>0
118
	 * @return 0 if x<0, p<=0, q<=0 or p+q>2.55E305 and 1 if x>1 to avoid errors and over/underflow
119
	 */
120
	private static function _incompleteBeta($x, $p, $q) {
121
		if ($x <= 0.0) {
122
			return 0.0;
123
		} elseif ($x >= 1.0) {
124
			return 1.0;
125
		} elseif (($p <= 0.0) || ($q <= 0.0) || (($p + $q) > LOG_GAMMA_X_MAX_VALUE)) {
126
			return 0.0;
127
		}
128
		$beta_gam = exp((0 - self::_logBeta($p, $q)) + $p * log($x) + $q * log(1.0 - $x));
129
		if ($x < ($p + 1.0) / ($p + $q + 2.0)) {
130
			return $beta_gam * self::_betaFraction($x, $p, $q) / $p;
131
		} else {
132
			return 1.0 - ($beta_gam * self::_betaFraction(1 - $x, $q, $p) / $q);
133
		}
134
	}	//	function _incompleteBeta()
135
 
136
 
137
	// Function cache for _logBeta function
138
	private static $_logBetaCache_p			= 0.0;
139
	private static $_logBetaCache_q			= 0.0;
140
	private static $_logBetaCache_result	= 0.0;
141
 
142
	/**
143
	 * The natural logarithm of the beta function.
144
	 *
145
	 * @param p require p>0
146
	 * @param q require q>0
147
	 * @return 0 if p<=0, q<=0 or p+q>2.55E305 to avoid errors and over/underflow
148
	 * @author Jaco van Kooten
149
	 */
150
	private static function _logBeta($p, $q) {
151
		if ($p != self::$_logBetaCache_p || $q != self::$_logBetaCache_q) {
152
			self::$_logBetaCache_p = $p;
153
			self::$_logBetaCache_q = $q;
154
			if (($p <= 0.0) || ($q <= 0.0) || (($p + $q) > LOG_GAMMA_X_MAX_VALUE)) {
155
				self::$_logBetaCache_result = 0.0;
156
			} else {
157
				self::$_logBetaCache_result = self::_logGamma($p) + self::_logGamma($q) - self::_logGamma($p + $q);
158
			}
159
		}
160
		return self::$_logBetaCache_result;
161
	}	//	function _logBeta()
162
 
163
 
164
	/**
165
	 * Evaluates of continued fraction part of incomplete beta function.
166
	 * Based on an idea from Numerical Recipes (W.H. Press et al, 1992).
167
	 * @author Jaco van Kooten
168
	 */
169
	private static function _betaFraction($x, $p, $q) {
170
		$c = 1.0;
171
		$sum_pq = $p + $q;
172
		$p_plus = $p + 1.0;
173
		$p_minus = $p - 1.0;
174
		$h = 1.0 - $sum_pq * $x / $p_plus;
175
		if (abs($h) < XMININ) {
176
			$h = XMININ;
177
		}
178
		$h = 1.0 / $h;
179
		$frac = $h;
180
		$m	 = 1;
181
		$delta = 0.0;
182
		while ($m <= MAX_ITERATIONS && abs($delta-1.0) > PRECISION ) {
183
			$m2 = 2 * $m;
184
			// even index for d
185
			$d = $m * ($q - $m) * $x / ( ($p_minus + $m2) * ($p + $m2));
186
			$h = 1.0 + $d * $h;
187
			if (abs($h) < XMININ) {
188
				$h = XMININ;
189
			}
190
			$h = 1.0 / $h;
191
			$c = 1.0 + $d / $c;
192
			if (abs($c) < XMININ) {
193
				$c = XMININ;
194
			}
195
			$frac *= $h * $c;
196
			// odd index for d
197
			$d = -($p + $m) * ($sum_pq + $m) * $x / (($p + $m2) * ($p_plus + $m2));
198
			$h = 1.0 + $d * $h;
199
			if (abs($h) < XMININ) {
200
				$h = XMININ;
201
			}
202
			$h = 1.0 / $h;
203
			$c = 1.0 + $d / $c;
204
			if (abs($c) < XMININ) {
205
				$c = XMININ;
206
			}
207
			$delta = $h * $c;
208
			$frac *= $delta;
209
			++$m;
210
		}
211
		return $frac;
212
	}	//	function _betaFraction()
213
 
214
 
215
	/**
216
	 * logGamma function
217
	 *
218
	 * @version 1.1
219
	 * @author Jaco van Kooten
220
	 *
221
	 * Original author was Jaco van Kooten. Ported to PHP by Paul Meagher.
222
	 *
223
	 * The natural logarithm of the gamma function. <br />
224
	 * Based on public domain NETLIB (Fortran) code by W. J. Cody and L. Stoltz <br />
225
	 * Applied Mathematics Division <br />
226
	 * Argonne National Laboratory <br />
227
	 * Argonne, IL 60439 <br />
228
	 * <p>
229
	 * References:
230
	 * <ol>
231
	 * <li>W. J. Cody and K. E. Hillstrom, 'Chebyshev Approximations for the Natural
232
	 *	 Logarithm of the Gamma Function,' Math. Comp. 21, 1967, pp. 198-203.</li>
233
	 * <li>K. E. Hillstrom, ANL/AMD Program ANLC366S, DGAMMA/DLGAMA, May, 1969.</li>
234
	 * <li>Hart, Et. Al., Computer Approximations, Wiley and sons, New York, 1968.</li>
235
	 * </ol>
236
	 * </p>
237
	 * <p>
238
	 * From the original documentation:
239
	 * </p>
240
	 * <p>
241
	 * This routine calculates the LOG(GAMMA) function for a positive real argument X.
242
	 * Computation is based on an algorithm outlined in references 1 and 2.
243
	 * The program uses rational functions that theoretically approximate LOG(GAMMA)
244
	 * to at least 18 significant decimal digits. The approximation for X > 12 is from
245
	 * reference 3, while approximations for X < 12.0 are similar to those in reference
246
	 * 1, but are unpublished. The accuracy achieved depends on the arithmetic system,
247
	 * the compiler, the intrinsic functions, and proper selection of the
248
	 * machine-dependent constants.
249
	 * </p>
250
	 * <p>
251
	 * Error returns: <br />
252
	 * The program returns the value XINF for X .LE. 0.0 or when overflow would occur.
253
	 * The computation is believed to be free of underflow and overflow.
254
	 * </p>
255
	 * @return MAX_VALUE for x < 0.0 or when overflow would occur, i.e. x > 2.55E305
256
	 */
257
 
258
	// Function cache for logGamma
259
	private static $_logGammaCache_result	= 0.0;
260
	private static $_logGammaCache_x		= 0.0;
261
 
262
	private static function _logGamma($x) {
263
		// Log Gamma related constants
264
		static $lg_d1 = -0.5772156649015328605195174;
265
		static $lg_d2 = 0.4227843350984671393993777;
266
		static $lg_d4 = 1.791759469228055000094023;
267
 
268
		static $lg_p1 = array(	4.945235359296727046734888,
269
								201.8112620856775083915565,
270
								2290.838373831346393026739,
271
								11319.67205903380828685045,
272
								28557.24635671635335736389,
273
								38484.96228443793359990269,
274
								26377.48787624195437963534,
275
								7225.813979700288197698961 );
276
		static $lg_p2 = array(	4.974607845568932035012064,
277
								542.4138599891070494101986,
278
								15506.93864978364947665077,
279
								184793.2904445632425417223,
280
								1088204.76946882876749847,
281
								3338152.967987029735917223,
282
								5106661.678927352456275255,
283
								3074109.054850539556250927 );
284
		static $lg_p4 = array(	14745.02166059939948905062,
285
								2426813.369486704502836312,
286
								121475557.4045093227939592,
287
								2663432449.630976949898078,
288
								29403789566.34553899906876,
289
								170266573776.5398868392998,
290
								492612579337.743088758812,
291
								560625185622.3951465078242 );
292
 
293
		static $lg_q1 = array(	67.48212550303777196073036,
294
								1113.332393857199323513008,
295
								7738.757056935398733233834,
296
								27639.87074403340708898585,
297
								54993.10206226157329794414,
298
								61611.22180066002127833352,
299
								36351.27591501940507276287,
300
								8785.536302431013170870835 );
301
		static $lg_q2 = array(	183.0328399370592604055942,
302
								7765.049321445005871323047,
303
								133190.3827966074194402448,
304
								1136705.821321969608938755,
305
								5267964.117437946917577538,
306
								13467014.54311101692290052,
307
								17827365.30353274213975932,
308
								9533095.591844353613395747 );
309
		static $lg_q4 = array(	2690.530175870899333379843,
310
								639388.5654300092398984238,
311
								41355999.30241388052042842,
312
								1120872109.61614794137657,
313
								14886137286.78813811542398,
314
								101680358627.2438228077304,
315
								341747634550.7377132798597,
316
								446315818741.9713286462081 );
317
 
318
		static $lg_c  = array(	-0.001910444077728,
319
								8.4171387781295e-4,
320
								-5.952379913043012e-4,
321
								7.93650793500350248e-4,
322
								-0.002777777777777681622553,
323
								0.08333333333333333331554247,
324
								0.0057083835261 );
325
 
326
	// Rough estimate of the fourth root of logGamma_xBig
327
	static $lg_frtbig = 2.25e76;
328
	static $pnt68	 = 0.6796875;
329
 
330
 
331
	if ($x == self::$_logGammaCache_x) {
332
		return self::$_logGammaCache_result;
333
	}
334
	$y = $x;
335
	if ($y > 0.0 && $y <= LOG_GAMMA_X_MAX_VALUE) {
336
		if ($y <= EPS) {
337
			$res = -log(y);
338
		} elseif ($y <= 1.5) {
339
			// ---------------------
340
			//	EPS .LT. X .LE. 1.5
341
			// ---------------------
342
			if ($y < $pnt68) {
343
				$corr = -log($y);
344
				$xm1 = $y;
345
			} else {
346
				$corr = 0.0;
347
				$xm1 = $y - 1.0;
348
			}
349
			if ($y <= 0.5 || $y >= $pnt68) {
350
				$xden = 1.0;
351
				$xnum = 0.0;
352
				for ($i = 0; $i < 8; ++$i) {
353
					$xnum = $xnum * $xm1 + $lg_p1[$i];
354
					$xden = $xden * $xm1 + $lg_q1[$i];
355
				}
356
				$res = $corr + $xm1 * ($lg_d1 + $xm1 * ($xnum / $xden));
357
			} else {
358
				$xm2 = $y - 1.0;
359
				$xden = 1.0;
360
				$xnum = 0.0;
361
				for ($i = 0; $i < 8; ++$i) {
362
					$xnum = $xnum * $xm2 + $lg_p2[$i];
363
					$xden = $xden * $xm2 + $lg_q2[$i];
364
				}
365
				$res = $corr + $xm2 * ($lg_d2 + $xm2 * ($xnum / $xden));
366
			}
367
		} elseif ($y <= 4.0) {
368
			// ---------------------
369
			//	1.5 .LT. X .LE. 4.0
370
			// ---------------------
371
			$xm2 = $y - 2.0;
372
			$xden = 1.0;
373
			$xnum = 0.0;
374
			for ($i = 0; $i < 8; ++$i) {
375
				$xnum = $xnum * $xm2 + $lg_p2[$i];
376
				$xden = $xden * $xm2 + $lg_q2[$i];
377
			}
378
			$res = $xm2 * ($lg_d2 + $xm2 * ($xnum / $xden));
379
		} elseif ($y <= 12.0) {
380
			// ----------------------
381
			//	4.0 .LT. X .LE. 12.0
382
			// ----------------------
383
			$xm4 = $y - 4.0;
384
			$xden = -1.0;
385
			$xnum = 0.0;
386
			for ($i = 0; $i < 8; ++$i) {
387
				$xnum = $xnum * $xm4 + $lg_p4[$i];
388
				$xden = $xden * $xm4 + $lg_q4[$i];
389
			}
390
			$res = $lg_d4 + $xm4 * ($xnum / $xden);
391
		} else {
392
			// ---------------------------------
393
			//	Evaluate for argument .GE. 12.0
394
			// ---------------------------------
395
			$res = 0.0;
396
			if ($y <= $lg_frtbig) {
397
				$res = $lg_c[6];
398
				$ysq = $y * $y;
399
				for ($i = 0; $i < 6; ++$i)
400
					$res = $res / $ysq + $lg_c[$i];
401
				}
402
				$res /= $y;
403
				$corr = log($y);
404
				$res = $res + log(SQRT2PI) - 0.5 * $corr;
405
				$res += $y * ($corr - 1.0);
406
			}
407
		} else {
408
			// --------------------------
409
			//	Return for bad arguments
410
			// --------------------------
411
			$res = MAX_VALUE;
412
		}
413
		// ------------------------------
414
		//	Final adjustments and return
415
		// ------------------------------
416
		self::$_logGammaCache_x = $x;
417
		self::$_logGammaCache_result = $res;
418
		return $res;
419
	}	//	function _logGamma()
420
 
421
 
422
	//
423
	//	Private implementation of the incomplete Gamma function
424
	//
425
	private static function _incompleteGamma($a,$x) {
426
		static $max = 32;
427
		$summer = 0;
428
		for ($n=0; $n<=$max; ++$n) {
429
			$divisor = $a;
430
			for ($i=1; $i<=$n; ++$i) {
431
				$divisor *= ($a + $i);
432
			}
433
			$summer += (pow($x,$n) / $divisor);
434
		}
435
		return pow($x,$a) * exp(0-$x) * $summer;
436
	}	//	function _incompleteGamma()
437
 
438
 
439
	//
440
	//	Private implementation of the Gamma function
441
	//
442
	private static function _gamma($data) {
443
		if ($data == 0.0) return 0;
444
 
445
		static $p0 = 1.000000000190015;
446
		static $p = array ( 1 => 76.18009172947146,
447
							2 => -86.50532032941677,
448
							3 => 24.01409824083091,
449
							4 => -1.231739572450155,
450
							5 => 1.208650973866179e-3,
451
							6 => -5.395239384953e-6
452
						  );
453
 
454
		$y = $x = $data;
455
		$tmp = $x + 5.5;
456
		$tmp -= ($x + 0.5) * log($tmp);
457
 
458
		$summer = $p0;
459
		for ($j=1;$j<=6;++$j) {
460
			$summer += ($p[$j] / ++$y);
461
		}
462
		return exp(0 - $tmp + log(SQRT2PI * $summer / $x));
463
	}	//	function _gamma()
464
 
465
 
466
	/***************************************************************************
467
	 *								inverse_ncdf.php
468
	 *							-------------------
469
	 *	begin				: Friday, January 16, 2004
470
	 *	copyright			: (C) 2004 Michael Nickerson
471
	 *	email				: nickersonm@yahoo.com
472
	 *
473
	 ***************************************************************************/
474
	private static function _inverse_ncdf($p) {
475
		//	Inverse ncdf approximation by Peter J. Acklam, implementation adapted to
476
		//	PHP by Michael Nickerson, using Dr. Thomas Ziegler's C implementation as
477
		//	a guide. http://home.online.no/~pjacklam/notes/invnorm/index.html
478
		//	I have not checked the accuracy of this implementation. Be aware that PHP
479
		//	will truncate the coeficcients to 14 digits.
480
 
481
		//	You have permission to use and distribute this function freely for
482
		//	whatever purpose you want, but please show common courtesy and give credit
483
		//	where credit is due.
484
 
485
		//	Input paramater is $p - probability - where 0 < p < 1.
486
 
487
		//	Coefficients in rational approximations
488
		static $a = array(	1 => -3.969683028665376e+01,
489
							2 => 2.209460984245205e+02,
490
							3 => -2.759285104469687e+02,
491
							4 => 1.383577518672690e+02,
492
							5 => -3.066479806614716e+01,
493
							6 => 2.506628277459239e+00
494
						 );
495
 
496
		static $b = array(	1 => -5.447609879822406e+01,
497
							2 => 1.615858368580409e+02,
498
							3 => -1.556989798598866e+02,
499
							4 => 6.680131188771972e+01,
500
							5 => -1.328068155288572e+01
501
						 );
502
 
503
		static $c = array(	1 => -7.784894002430293e-03,
504
							2 => -3.223964580411365e-01,
505
							3 => -2.400758277161838e+00,
506
							4 => -2.549732539343734e+00,
507
							5 => 4.374664141464968e+00,
508
							6 => 2.938163982698783e+00
509
						 );
510
 
511
		static $d = array(	1 => 7.784695709041462e-03,
512
							2 => 3.224671290700398e-01,
513
							3 => 2.445134137142996e+00,
514
							4 => 3.754408661907416e+00
515
						 );
516
 
517
		//	Define lower and upper region break-points.
518
		$p_low = 0.02425;			//Use lower region approx. below this
519
		$p_high = 1 - $p_low;		//Use upper region approx. above this
520
 
521
		if (0 < $p && $p < $p_low) {
522
			//	Rational approximation for lower region.
523
			$q = sqrt(-2 * log($p));
524
			return ((((($c[1] * $q + $c[2]) * $q + $c[3]) * $q + $c[4]) * $q + $c[5]) * $q + $c[6]) /
525
					(((($d[1] * $q + $d[2]) * $q + $d[3]) * $q + $d[4]) * $q + 1);
526
		} elseif ($p_low <= $p && $p <= $p_high) {
527
			//	Rational approximation for central region.
528
			$q = $p - 0.5;
529
			$r = $q * $q;
530
			return ((((($a[1] * $r + $a[2]) * $r + $a[3]) * $r + $a[4]) * $r + $a[5]) * $r + $a[6]) * $q /
531
				   ((((($b[1] * $r + $b[2]) * $r + $b[3]) * $r + $b[4]) * $r + $b[5]) * $r + 1);
532
		} elseif ($p_high < $p && $p < 1) {
533
			//	Rational approximation for upper region.
534
			$q = sqrt(-2 * log(1 - $p));
535
			return -((((($c[1] * $q + $c[2]) * $q + $c[3]) * $q + $c[4]) * $q + $c[5]) * $q + $c[6]) /
536
					 (((($d[1] * $q + $d[2]) * $q + $d[3]) * $q + $d[4]) * $q + 1);
537
		}
538
		//	If 0 < p < 1, return a null value
539
		return PHPExcel_Calculation_Functions::NULL();
540
	}	//	function _inverse_ncdf()
541
 
542
 
543
	private static function _inverse_ncdf2($prob) {
544
		//	Approximation of inverse standard normal CDF developed by
545
		//	B. Moro, "The Full Monte," Risk 8(2), Feb 1995, 57-58.
546
 
547
		$a1 = 2.50662823884;
548
		$a2 = -18.61500062529;
549
		$a3 = 41.39119773534;
550
		$a4 = -25.44106049637;
551
 
552
		$b1 = -8.4735109309;
553
		$b2 = 23.08336743743;
554
		$b3 = -21.06224101826;
555
		$b4 = 3.13082909833;
556
 
557
		$c1 = 0.337475482272615;
558
		$c2 = 0.976169019091719;
559
		$c3 = 0.160797971491821;
560
		$c4 = 2.76438810333863E-02;
561
		$c5 = 3.8405729373609E-03;
562
		$c6 = 3.951896511919E-04;
563
		$c7 = 3.21767881768E-05;
564
		$c8 = 2.888167364E-07;
565
		$c9 = 3.960315187E-07;
566
 
567
		$y = $prob - 0.5;
568
		if (abs($y) < 0.42) {
569
			$z = ($y * $y);
570
			$z = $y * ((($a4 * $z + $a3) * $z + $a2) * $z + $a1) / (((($b4 * $z + $b3) * $z + $b2) * $z + $b1) * $z + 1);
571
		} else {
572
			if ($y > 0) {
573
				$z = log(-log(1 - $prob));
574
			} else {
575
				$z = log(-log($prob));
576
			}
577
			$z = $c1 + $z * ($c2 + $z * ($c3 + $z * ($c4 + $z * ($c5 + $z * ($c6 + $z * ($c7 + $z * ($c8 + $z * $c9)))))));
578
			if ($y < 0) {
579
				$z = -$z;
580
			}
581
		}
582
		return $z;
583
	}	//	function _inverse_ncdf2()
584
 
585
 
586
	private static function _inverse_ncdf3($p) {
587
		//	ALGORITHM AS241 APPL. STATIST. (1988) VOL. 37, NO. 3.
588
		//	Produces the normal deviate Z corresponding to a given lower
589
		//	tail area of P; Z is accurate to about 1 part in 10**16.
590
		//
591
		//	This is a PHP version of the original FORTRAN code that can
592
		//	be found at http://lib.stat.cmu.edu/apstat/
593
		$split1 = 0.425;
594
		$split2 = 5;
595
		$const1 = 0.180625;
596
		$const2 = 1.6;
597
 
598
		//	coefficients for p close to 0.5
599
		$a0 = 3.3871328727963666080;
600
		$a1 = 1.3314166789178437745E+2;
601
		$a2 = 1.9715909503065514427E+3;
602
		$a3 = 1.3731693765509461125E+4;
603
		$a4 = 4.5921953931549871457E+4;
604
		$a5 = 6.7265770927008700853E+4;
605
		$a6 = 3.3430575583588128105E+4;
606
		$a7 = 2.5090809287301226727E+3;
607
 
608
		$b1 = 4.2313330701600911252E+1;
609
		$b2 = 6.8718700749205790830E+2;
610
		$b3 = 5.3941960214247511077E+3;
611
		$b4 = 2.1213794301586595867E+4;
612
		$b5 = 3.9307895800092710610E+4;
613
		$b6 = 2.8729085735721942674E+4;
614
		$b7 = 5.2264952788528545610E+3;
615
 
616
		//	coefficients for p not close to 0, 0.5 or 1.
617
		$c0 = 1.42343711074968357734;
618
		$c1 = 4.63033784615654529590;
619
		$c2 = 5.76949722146069140550;
620
		$c3 = 3.64784832476320460504;
621
		$c4 = 1.27045825245236838258;
622
		$c5 = 2.41780725177450611770E-1;
623
		$c6 = 2.27238449892691845833E-2;
624
		$c7 = 7.74545014278341407640E-4;
625
 
626
		$d1 = 2.05319162663775882187;
627
		$d2 = 1.67638483018380384940;
628
		$d3 = 6.89767334985100004550E-1;
629
		$d4 = 1.48103976427480074590E-1;
630
		$d5 = 1.51986665636164571966E-2;
631
		$d6 = 5.47593808499534494600E-4;
632
		$d7 = 1.05075007164441684324E-9;
633
 
634
		//	coefficients for p near 0 or 1.
635
		$e0 = 6.65790464350110377720;
636
		$e1 = 5.46378491116411436990;
637
		$e2 = 1.78482653991729133580;
638
		$e3 = 2.96560571828504891230E-1;
639
		$e4 = 2.65321895265761230930E-2;
640
		$e5 = 1.24266094738807843860E-3;
641
		$e6 = 2.71155556874348757815E-5;
642
		$e7 = 2.01033439929228813265E-7;
643
 
644
		$f1 = 5.99832206555887937690E-1;
645
		$f2 = 1.36929880922735805310E-1;
646
		$f3 = 1.48753612908506148525E-2;
647
		$f4 = 7.86869131145613259100E-4;
648
		$f5 = 1.84631831751005468180E-5;
649
		$f6 = 1.42151175831644588870E-7;
650
		$f7 = 2.04426310338993978564E-15;
651
 
652
		$q = $p - 0.5;
653
 
654
		//	computation for p close to 0.5
655
		if (abs($q) <= split1) {
656
			$R = $const1 - $q * $q;
657
			$z = $q * ((((((($a7 * $R + $a6) * $R + $a5) * $R + $a4) * $R + $a3) * $R + $a2) * $R + $a1) * $R + $a0) /
658
					  ((((((($b7 * $R + $b6) * $R + $b5) * $R + $b4) * $R + $b3) * $R + $b2) * $R + $b1) * $R + 1);
659
		} else {
660
			if ($q < 0) {
661
				$R = $p;
662
			} else {
663
				$R = 1 - $p;
664
			}
665
			$R = pow(-log($R),2);
666
 
667
			//	computation for p not close to 0, 0.5 or 1.
668
			If ($R <= $split2) {
669
				$R = $R - $const2;
670
				$z = ((((((($c7 * $R + $c6) * $R + $c5) * $R + $c4) * $R + $c3) * $R + $c2) * $R + $c1) * $R + $c0) /
671
					 ((((((($d7 * $R + $d6) * $R + $d5) * $R + $d4) * $R + $d3) * $R + $d2) * $R + $d1) * $R + 1);
672
			} else {
673
			//	computation for p near 0 or 1.
674
				$R = $R - $split2;
675
				$z = ((((((($e7 * $R + $e6) * $R + $e5) * $R + $e4) * $R + $e3) * $R + $e2) * $R + $e1) * $R + $e0) /
676
					 ((((((($f7 * $R + $f6) * $R + $f5) * $R + $f4) * $R + $f3) * $R + $f2) * $R + $f1) * $R + 1);
677
			}
678
			if ($q < 0) {
679
				$z = -$z;
680
			}
681
		}
682
		return $z;
683
	}	//	function _inverse_ncdf3()
684
 
685
 
686
	/**
687
	 * AVEDEV
688
	 *
689
	 * Returns the average of the absolute deviations of data points from their mean.
690
	 * AVEDEV is a measure of the variability in a data set.
691
	 *
692
	 * Excel Function:
693
	 *		AVEDEV(value1[,value2[, ...]])
694
	 *
695
	 * @access	public
696
	 * @category Statistical Functions
697
	 * @param	mixed		$arg,...		Data values
698
	 * @return	float
699
	 */
700
	public static function AVEDEV() {
701
		$aArgs = PHPExcel_Calculation_Functions::flattenArrayIndexed(func_get_args());
702
 
703
		// Return value
704
		$returnValue = null;
705
 
706
		$aMean = self::AVERAGE($aArgs);
707
		if ($aMean != PHPExcel_Calculation_Functions::DIV0()) {
708
			$aCount = 0;
709
			foreach ($aArgs as $k => $arg) {
710
				if ((is_bool($arg)) &&
711
					((!PHPExcel_Calculation_Functions::isCellValue($k)) || (PHPExcel_Calculation_Functions::getCompatibilityMode() == PHPExcel_Calculation_Functions::COMPATIBILITY_OPENOFFICE))) {
712
					$arg = (integer) $arg;
713
				}
714
				// Is it a numeric value?
715
				if ((is_numeric($arg)) && (!is_string($arg))) {
716
					if (is_null($returnValue)) {
717
						$returnValue = abs($arg - $aMean);
718
					} else {
719
						$returnValue += abs($arg - $aMean);
720
					}
721
					++$aCount;
722
				}
723
			}
724
 
725
			// Return
726
			if ($aCount == 0) {
727
				return PHPExcel_Calculation_Functions::DIV0();
728
			}
729
			return $returnValue / $aCount;
730
		}
731
		return PHPExcel_Calculation_Functions::NaN();
732
	}	//	function AVEDEV()
733
 
734
 
735
	/**
736
	 * AVERAGE
737
	 *
738
	 * Returns the average (arithmetic mean) of the arguments
739
	 *
740
	 * Excel Function:
741
	 *		AVERAGE(value1[,value2[, ...]])
742
	 *
743
	 * @access	public
744
	 * @category Statistical Functions
745
	 * @param	mixed		$arg,...		Data values
746
	 * @return	float
747
	 */
748
	public static function AVERAGE() {
749
		$returnValue = $aCount = 0;
750
 
751
		// Loop through arguments
752
		foreach (PHPExcel_Calculation_Functions::flattenArrayIndexed(func_get_args()) as $k => $arg) {
753
			if ((is_bool($arg)) &&
754
				((!PHPExcel_Calculation_Functions::isCellValue($k)) || (PHPExcel_Calculation_Functions::getCompatibilityMode() == PHPExcel_Calculation_Functions::COMPATIBILITY_OPENOFFICE))) {
755
				$arg = (integer) $arg;
756
			}
757
			// Is it a numeric value?
758
			if ((is_numeric($arg)) && (!is_string($arg))) {
759
				if (is_null($returnValue)) {
760
					$returnValue = $arg;
761
				} else {
762
					$returnValue += $arg;
763
				}
764
				++$aCount;
765
			}
766
		}
767
 
768
		// Return
769
		if ($aCount > 0) {
770
			return $returnValue / $aCount;
771
		} else {
772
			return PHPExcel_Calculation_Functions::DIV0();
773
		}
774
	}	//	function AVERAGE()
775
 
776
 
777
	/**
778
	 * AVERAGEA
779
	 *
780
	 * Returns the average of its arguments, including numbers, text, and logical values
781
	 *
782
	 * Excel Function:
783
	 *		AVERAGEA(value1[,value2[, ...]])
784
	 *
785
	 * @access	public
786
	 * @category Statistical Functions
787
	 * @param	mixed		$arg,...		Data values
788
	 * @return	float
789
	 */
790
	public static function AVERAGEA() {
791
		// Return value
792
		$returnValue = null;
793
 
794
		$aCount = 0;
795
		// Loop through arguments
796
		foreach (PHPExcel_Calculation_Functions::flattenArrayIndexed(func_get_args()) as $k => $arg) {
797
			if ((is_bool($arg)) &&
798
				(!PHPExcel_Calculation_Functions::isMatrixValue($k))) {
799
			} else {
800
				if ((is_numeric($arg)) || (is_bool($arg)) || ((is_string($arg) && ($arg != '')))) {
801
					if (is_bool($arg)) {
802
						$arg = (integer) $arg;
803
					} elseif (is_string($arg)) {
804
						$arg = 0;
805
					}
806
					if (is_null($returnValue)) {
807
						$returnValue = $arg;
808
					} else {
809
						$returnValue += $arg;
810
					}
811
					++$aCount;
812
				}
813
			}
814
		}
815
 
816
		// Return
817
		if ($aCount > 0) {
818
			return $returnValue / $aCount;
819
		} else {
820
			return PHPExcel_Calculation_Functions::DIV0();
821
		}
822
	}	//	function AVERAGEA()
823
 
824
 
825
	/**
826
	 * AVERAGEIF
827
	 *
828
	 * Returns the average value from a range of cells that contain numbers within the list of arguments
829
	 *
830
	 * Excel Function:
831
	 *		AVERAGEIF(value1[,value2[, ...]],condition)
832
	 *
833
	 * @access	public
834
	 * @category Mathematical and Trigonometric Functions
835
	 * @param	mixed		$arg,...		Data values
836
	 * @param	string		$condition		The criteria that defines which cells will be checked.
837
	 * @param	mixed[]		$averageArgs	Data values
838
	 * @return	float
839
	 */
840
	public static function AVERAGEIF($aArgs,$condition,$averageArgs = array()) {
841
		// Return value
842
		$returnValue = 0;
843
 
844
		$aArgs = PHPExcel_Calculation_Functions::flattenArray($aArgs);
845
		$averageArgs = PHPExcel_Calculation_Functions::flattenArray($averageArgs);
846
		if (empty($averageArgs)) {
847
			$averageArgs = $aArgs;
848
		}
849
		$condition = PHPExcel_Calculation_Functions::_ifCondition($condition);
850
		// Loop through arguments
851
		$aCount = 0;
852
		foreach ($aArgs as $key => $arg) {
853
			if (!is_numeric($arg)) { $arg = PHPExcel_Calculation::_wrapResult(strtoupper($arg)); }
854
			$testCondition = '='.$arg.$condition;
855
			if (PHPExcel_Calculation::getInstance()->_calculateFormulaValue($testCondition)) {
856
				if ((is_null($returnValue)) || ($arg > $returnValue)) {
857
					$returnValue += $arg;
858
					++$aCount;
859
				}
860
			}
861
		}
862
 
863
		// Return
864
		if ($aCount > 0) {
865
			return $returnValue / $aCount;
866
		} else {
867
			return PHPExcel_Calculation_Functions::DIV0();
868
		}
869
	}	//	function AVERAGEIF()
870
 
871
 
872
	/**
873
	 * BETADIST
874
	 *
875
	 * Returns the beta distribution.
876
	 *
877
	 * @param	float		$value			Value at which you want to evaluate the distribution
878
	 * @param	float		$alpha			Parameter to the distribution
879
	 * @param	float		$beta			Parameter to the distribution
880
	 * @param	boolean		$cumulative
881
	 * @return	float
882
	 *
883
	 */
884
	public static function BETADIST($value,$alpha,$beta,$rMin=0,$rMax=1) {
885
		$value	= PHPExcel_Calculation_Functions::flattenSingleValue($value);
886
		$alpha	= PHPExcel_Calculation_Functions::flattenSingleValue($alpha);
887
		$beta	= PHPExcel_Calculation_Functions::flattenSingleValue($beta);
888
		$rMin	= PHPExcel_Calculation_Functions::flattenSingleValue($rMin);
889
		$rMax	= PHPExcel_Calculation_Functions::flattenSingleValue($rMax);
890
 
891
		if ((is_numeric($value)) && (is_numeric($alpha)) && (is_numeric($beta)) && (is_numeric($rMin)) && (is_numeric($rMax))) {
892
			if (($value < $rMin) || ($value > $rMax) || ($alpha <= 0) || ($beta <= 0) || ($rMin == $rMax)) {
893
				return PHPExcel_Calculation_Functions::NaN();
894
			}
895
			if ($rMin > $rMax) {
896
				$tmp = $rMin;
897
				$rMin = $rMax;
898
				$rMax = $tmp;
899
			}
900
			$value -= $rMin;
901
			$value /= ($rMax - $rMin);
902
			return self::_incompleteBeta($value,$alpha,$beta);
903
		}
904
		return PHPExcel_Calculation_Functions::VALUE();
905
	}	//	function BETADIST()
906
 
907
 
908
	/**
909
	 * BETAINV
910
	 *
911
	 * Returns the inverse of the beta distribution.
912
	 *
913
	 * @param	float		$probability	Probability at which you want to evaluate the distribution
914
	 * @param	float		$alpha			Parameter to the distribution
915
	 * @param	float		$beta			Parameter to the distribution
916
	 * @param	float		$rMin			Minimum value
917
	 * @param	float		$rMax			Maximum value
918
	 * @param	boolean		$cumulative
919
	 * @return	float
920
	 *
921
	 */
922
	public static function BETAINV($probability,$alpha,$beta,$rMin=0,$rMax=1) {
923
		$probability	= PHPExcel_Calculation_Functions::flattenSingleValue($probability);
924
		$alpha			= PHPExcel_Calculation_Functions::flattenSingleValue($alpha);
925
		$beta			= PHPExcel_Calculation_Functions::flattenSingleValue($beta);
926
		$rMin			= PHPExcel_Calculation_Functions::flattenSingleValue($rMin);
927
		$rMax			= PHPExcel_Calculation_Functions::flattenSingleValue($rMax);
928
 
929
		if ((is_numeric($probability)) && (is_numeric($alpha)) && (is_numeric($beta)) && (is_numeric($rMin)) && (is_numeric($rMax))) {
930
			if (($alpha <= 0) || ($beta <= 0) || ($rMin == $rMax) || ($probability <= 0) || ($probability > 1)) {
931
				return PHPExcel_Calculation_Functions::NaN();
932
			}
933
			if ($rMin > $rMax) {
934
				$tmp = $rMin;
935
				$rMin = $rMax;
936
				$rMax = $tmp;
937
			}
938
			$a = 0;
939
			$b = 2;
940
 
941
			$i = 0;
942
			while ((($b - $a) > PRECISION) && ($i++ < MAX_ITERATIONS)) {
943
				$guess = ($a + $b) / 2;
944
				$result = self::BETADIST($guess, $alpha, $beta);
945
				if (($result == $probability) || ($result == 0)) {
946
					$b = $a;
947
				} elseif ($result > $probability) {
948
					$b = $guess;
949
				} else {
950
					$a = $guess;
951
				}
952
			}
953
			if ($i == MAX_ITERATIONS) {
954
				return PHPExcel_Calculation_Functions::NA();
955
			}
956
			return round($rMin + $guess * ($rMax - $rMin),12);
957
		}
958
		return PHPExcel_Calculation_Functions::VALUE();
959
	}	//	function BETAINV()
960
 
961
 
962
	/**
963
	 * BINOMDIST
964
	 *
965
	 * Returns the individual term binomial distribution probability. Use BINOMDIST in problems with
966
	 *		a fixed number of tests or trials, when the outcomes of any trial are only success or failure,
967
	 *		when trials are independent, and when the probability of success is constant throughout the
968
	 *		experiment. For example, BINOMDIST can calculate the probability that two of the next three
969
	 *		babies born are male.
970
	 *
971
	 * @param	float		$value			Number of successes in trials
972
	 * @param	float		$trials			Number of trials
973
	 * @param	float		$probability	Probability of success on each trial
974
	 * @param	boolean		$cumulative
975
	 * @return	float
976
	 *
977
	 * @todo	Cumulative distribution function
978
	 *
979
	 */
980
	public static function BINOMDIST($value, $trials, $probability, $cumulative) {
981
		$value			= floor(PHPExcel_Calculation_Functions::flattenSingleValue($value));
982
		$trials			= floor(PHPExcel_Calculation_Functions::flattenSingleValue($trials));
983
		$probability	= PHPExcel_Calculation_Functions::flattenSingleValue($probability);
984
 
985
		if ((is_numeric($value)) && (is_numeric($trials)) && (is_numeric($probability))) {
986
			if (($value < 0) || ($value > $trials)) {
987
				return PHPExcel_Calculation_Functions::NaN();
988
			}
989
			if (($probability < 0) || ($probability > 1)) {
990
				return PHPExcel_Calculation_Functions::NaN();
991
			}
992
			if ((is_numeric($cumulative)) || (is_bool($cumulative))) {
993
				if ($cumulative) {
994
					$summer = 0;
995
					for ($i = 0; $i <= $value; ++$i) {
996
						$summer += PHPExcel_Calculation_MathTrig::COMBIN($trials,$i) * pow($probability,$i) * pow(1 - $probability,$trials - $i);
997
					}
998
					return $summer;
999
				} else {
1000
					return PHPExcel_Calculation_MathTrig::COMBIN($trials,$value) * pow($probability,$value) * pow(1 - $probability,$trials - $value) ;
1001
				}
1002
			}
1003
		}
1004
		return PHPExcel_Calculation_Functions::VALUE();
1005
	}	//	function BINOMDIST()
1006
 
1007
 
1008
	/**
1009
	 * CHIDIST
1010
	 *
1011
	 * Returns the one-tailed probability of the chi-squared distribution.
1012
	 *
1013
	 * @param	float		$value			Value for the function
1014
	 * @param	float		$degrees		degrees of freedom
1015
	 * @return	float
1016
	 */
1017
	public static function CHIDIST($value, $degrees) {
1018
		$value		= PHPExcel_Calculation_Functions::flattenSingleValue($value);
1019
		$degrees	= floor(PHPExcel_Calculation_Functions::flattenSingleValue($degrees));
1020
 
1021
		if ((is_numeric($value)) && (is_numeric($degrees))) {
1022
			if ($degrees < 1) {
1023
				return PHPExcel_Calculation_Functions::NaN();
1024
			}
1025
			if ($value < 0) {
1026
				if (PHPExcel_Calculation_Functions::getCompatibilityMode() == PHPExcel_Calculation_Functions::COMPATIBILITY_GNUMERIC) {
1027
					return 1;
1028
				}
1029
				return PHPExcel_Calculation_Functions::NaN();
1030
			}
1031
			return 1 - (self::_incompleteGamma($degrees/2,$value/2) / self::_gamma($degrees/2));
1032
		}
1033
		return PHPExcel_Calculation_Functions::VALUE();
1034
	}	//	function CHIDIST()
1035
 
1036
 
1037
	/**
1038
	 * CHIINV
1039
	 *
1040
	 * Returns the one-tailed probability of the chi-squared distribution.
1041
	 *
1042
	 * @param	float		$probability	Probability for the function
1043
	 * @param	float		$degrees		degrees of freedom
1044
	 * @return	float
1045
	 */
1046
	public static function CHIINV($probability, $degrees) {
1047
		$probability	= PHPExcel_Calculation_Functions::flattenSingleValue($probability);
1048
		$degrees		= floor(PHPExcel_Calculation_Functions::flattenSingleValue($degrees));
1049
 
1050
		if ((is_numeric($probability)) && (is_numeric($degrees))) {
1051
 
1052
			$xLo = 100;
1053
			$xHi = 0;
1054
 
1055
			$x = $xNew = 1;
1056
			$dx	= 1;
1057
			$i = 0;
1058
 
1059
			while ((abs($dx) > PRECISION) && ($i++ < MAX_ITERATIONS)) {
1060
				// Apply Newton-Raphson step
1061
				$result = self::CHIDIST($x, $degrees);
1062
				$error = $result - $probability;
1063
				if ($error == 0.0) {
1064
					$dx = 0;
1065
				} elseif ($error < 0.0) {
1066
					$xLo = $x;
1067
				} else {
1068
					$xHi = $x;
1069
				}
1070
				// Avoid division by zero
1071
				if ($result != 0.0) {
1072
					$dx = $error / $result;
1073
					$xNew = $x - $dx;
1074
				}
1075
				// If the NR fails to converge (which for example may be the
1076
				// case if the initial guess is too rough) we apply a bisection
1077
				// step to determine a more narrow interval around the root.
1078
				if (($xNew < $xLo) || ($xNew > $xHi) || ($result == 0.0)) {
1079
					$xNew = ($xLo + $xHi) / 2;
1080
					$dx = $xNew - $x;
1081
				}
1082
				$x = $xNew;
1083
			}
1084
			if ($i == MAX_ITERATIONS) {
1085
				return PHPExcel_Calculation_Functions::NA();
1086
			}
1087
			return round($x,12);
1088
		}
1089
		return PHPExcel_Calculation_Functions::VALUE();
1090
	}	//	function CHIINV()
1091
 
1092
 
1093
	/**
1094
	 * CONFIDENCE
1095
	 *
1096
	 * Returns the confidence interval for a population mean
1097
	 *
1098
	 * @param	float		$alpha
1099
	 * @param	float		$stdDev		Standard Deviation
1100
	 * @param	float		$size
1101
	 * @return	float
1102
	 *
1103
	 */
1104
	public static function CONFIDENCE($alpha,$stdDev,$size) {
1105
		$alpha	= PHPExcel_Calculation_Functions::flattenSingleValue($alpha);
1106
		$stdDev	= PHPExcel_Calculation_Functions::flattenSingleValue($stdDev);
1107
		$size	= floor(PHPExcel_Calculation_Functions::flattenSingleValue($size));
1108
 
1109
		if ((is_numeric($alpha)) && (is_numeric($stdDev)) && (is_numeric($size))) {
1110
			if (($alpha <= 0) || ($alpha >= 1)) {
1111
				return PHPExcel_Calculation_Functions::NaN();
1112
			}
1113
			if (($stdDev <= 0) || ($size < 1)) {
1114
				return PHPExcel_Calculation_Functions::NaN();
1115
			}
1116
			return self::NORMSINV(1 - $alpha / 2) * $stdDev / sqrt($size);
1117
		}
1118
		return PHPExcel_Calculation_Functions::VALUE();
1119
	}	//	function CONFIDENCE()
1120
 
1121
 
1122
	/**
1123
	 * CORREL
1124
	 *
1125
	 * Returns covariance, the average of the products of deviations for each data point pair.
1126
	 *
1127
	 * @param	array of mixed		Data Series Y
1128
	 * @param	array of mixed		Data Series X
1129
	 * @return	float
1130
	 */
1131
	public static function CORREL($yValues,$xValues=null) {
1132
		if ((is_null($xValues)) || (!is_array($yValues)) || (!is_array($xValues))) {
1133
			return PHPExcel_Calculation_Functions::VALUE();
1134
		}
1135
		if (!self::_checkTrendArrays($yValues,$xValues)) {
1136
			return PHPExcel_Calculation_Functions::VALUE();
1137
		}
1138
		$yValueCount = count($yValues);
1139
		$xValueCount = count($xValues);
1140
 
1141
		if (($yValueCount == 0) || ($yValueCount != $xValueCount)) {
1142
			return PHPExcel_Calculation_Functions::NA();
1143
		} elseif ($yValueCount == 1) {
1144
			return PHPExcel_Calculation_Functions::DIV0();
1145
		}
1146
 
1147
		$bestFitLinear = trendClass::calculate(trendClass::TREND_LINEAR,$yValues,$xValues);
1148
		return $bestFitLinear->getCorrelation();
1149
	}	//	function CORREL()
1150
 
1151
 
1152
	/**
1153
	 * COUNT
1154
	 *
1155
	 * Counts the number of cells that contain numbers within the list of arguments
1156
	 *
1157
	 * Excel Function:
1158
	 *		COUNT(value1[,value2[, ...]])
1159
	 *
1160
	 * @access	public
1161
	 * @category Statistical Functions
1162
	 * @param	mixed		$arg,...		Data values
1163
	 * @return	int
1164
	 */
1165
	public static function COUNT() {
1166
		// Return value
1167
		$returnValue = 0;
1168
 
1169
		// Loop through arguments
1170
		$aArgs = PHPExcel_Calculation_Functions::flattenArrayIndexed(func_get_args());
1171
		foreach ($aArgs as $k => $arg) {
1172
			if ((is_bool($arg)) &&
1173
				((!PHPExcel_Calculation_Functions::isCellValue($k)) || (PHPExcel_Calculation_Functions::getCompatibilityMode() == PHPExcel_Calculation_Functions::COMPATIBILITY_OPENOFFICE))) {
1174
				$arg = (integer) $arg;
1175
			}
1176
			// Is it a numeric value?
1177
			if ((is_numeric($arg)) && (!is_string($arg))) {
1178
				++$returnValue;
1179
			}
1180
		}
1181
 
1182
		// Return
1183
		return $returnValue;
1184
	}	//	function COUNT()
1185
 
1186
 
1187
	/**
1188
	 * COUNTA
1189
	 *
1190
	 * Counts the number of cells that are not empty within the list of arguments
1191
	 *
1192
	 * Excel Function:
1193
	 *		COUNTA(value1[,value2[, ...]])
1194
	 *
1195
	 * @access	public
1196
	 * @category Statistical Functions
1197
	 * @param	mixed		$arg,...		Data values
1198
	 * @return	int
1199
	 */
1200
	public static function COUNTA() {
1201
		// Return value
1202
		$returnValue = 0;
1203
 
1204
		// Loop through arguments
1205
		$aArgs = PHPExcel_Calculation_Functions::flattenArray(func_get_args());
1206
		foreach ($aArgs as $arg) {
1207
			// Is it a numeric, boolean or string value?
1208
			if ((is_numeric($arg)) || (is_bool($arg)) || ((is_string($arg) && ($arg != '')))) {
1209
				++$returnValue;
1210
			}
1211
		}
1212
 
1213
		// Return
1214
		return $returnValue;
1215
	}	//	function COUNTA()
1216
 
1217
 
1218
	/**
1219
	 * COUNTBLANK
1220
	 *
1221
	 * Counts the number of empty cells within the list of arguments
1222
	 *
1223
	 * Excel Function:
1224
	 *		COUNTBLANK(value1[,value2[, ...]])
1225
	 *
1226
	 * @access	public
1227
	 * @category Statistical Functions
1228
	 * @param	mixed		$arg,...		Data values
1229
	 * @return	int
1230
	 */
1231
	public static function COUNTBLANK() {
1232
		// Return value
1233
		$returnValue = 0;
1234
 
1235
		// Loop through arguments
1236
		$aArgs = PHPExcel_Calculation_Functions::flattenArray(func_get_args());
1237
		foreach ($aArgs as $arg) {
1238
			// Is it a blank cell?
1239
			if ((is_null($arg)) || ((is_string($arg)) && ($arg == ''))) {
1240
				++$returnValue;
1241
			}
1242
		}
1243
 
1244
		// Return
1245
		return $returnValue;
1246
	}	//	function COUNTBLANK()
1247
 
1248
 
1249
	/**
1250
	 * COUNTIF
1251
	 *
1252
	 * Counts the number of cells that contain numbers within the list of arguments
1253
	 *
1254
	 * Excel Function:
1255
	 *		COUNTIF(value1[,value2[, ...]],condition)
1256
	 *
1257
	 * @access	public
1258
	 * @category Statistical Functions
1259
	 * @param	mixed		$arg,...		Data values
1260
	 * @param	string		$condition		The criteria that defines which cells will be counted.
1261
	 * @return	int
1262
	 */
1263
	public static function COUNTIF($aArgs,$condition) {
1264
		// Return value
1265
		$returnValue = 0;
1266
 
1267
		$aArgs = PHPExcel_Calculation_Functions::flattenArray($aArgs);
1268
		$condition = PHPExcel_Calculation_Functions::_ifCondition($condition);
1269
		// Loop through arguments
1270
		foreach ($aArgs as $arg) {
1271
			if (!is_numeric($arg)) { $arg = PHPExcel_Calculation::_wrapResult(strtoupper($arg)); }
1272
			$testCondition = '='.$arg.$condition;
1273
			if (PHPExcel_Calculation::getInstance()->_calculateFormulaValue($testCondition)) {
1274
				// Is it a value within our criteria
1275
				++$returnValue;
1276
			}
1277
		}
1278
 
1279
		// Return
1280
		return $returnValue;
1281
	}	//	function COUNTIF()
1282
 
1283
 
1284
	/**
1285
	 * COVAR
1286
	 *
1287
	 * Returns covariance, the average of the products of deviations for each data point pair.
1288
	 *
1289
	 * @param	array of mixed		Data Series Y
1290
	 * @param	array of mixed		Data Series X
1291
	 * @return	float
1292
	 */
1293
	public static function COVAR($yValues,$xValues) {
1294
		if (!self::_checkTrendArrays($yValues,$xValues)) {
1295
			return PHPExcel_Calculation_Functions::VALUE();
1296
		}
1297
		$yValueCount = count($yValues);
1298
		$xValueCount = count($xValues);
1299
 
1300
		if (($yValueCount == 0) || ($yValueCount != $xValueCount)) {
1301
			return PHPExcel_Calculation_Functions::NA();
1302
		} elseif ($yValueCount == 1) {
1303
			return PHPExcel_Calculation_Functions::DIV0();
1304
		}
1305
 
1306
		$bestFitLinear = trendClass::calculate(trendClass::TREND_LINEAR,$yValues,$xValues);
1307
		return $bestFitLinear->getCovariance();
1308
	}	//	function COVAR()
1309
 
1310
 
1311
	/**
1312
	 * CRITBINOM
1313
	 *
1314
	 * Returns the smallest value for which the cumulative binomial distribution is greater
1315
	 *		than or equal to a criterion value
1316
	 *
1317
	 * See http://support.microsoft.com/kb/828117/ for details of the algorithm used
1318
	 *
1319
	 * @param	float		$trials			number of Bernoulli trials
1320
	 * @param	float		$probability	probability of a success on each trial
1321
	 * @param	float		$alpha			criterion value
1322
	 * @return	int
1323
	 *
1324
	 * @todo	Warning. This implementation differs from the algorithm detailed on the MS
1325
	 *			web site in that $CumPGuessMinus1 = $CumPGuess - 1 rather than $CumPGuess - $PGuess
1326
	 *			This eliminates a potential endless loop error, but may have an adverse affect on the
1327
	 *			accuracy of the function (although all my tests have so far returned correct results).
1328
	 *
1329
	 */
1330
	public static function CRITBINOM($trials, $probability, $alpha) {
1331
		$trials			= floor(PHPExcel_Calculation_Functions::flattenSingleValue($trials));
1332
		$probability	= PHPExcel_Calculation_Functions::flattenSingleValue($probability);
1333
		$alpha			= PHPExcel_Calculation_Functions::flattenSingleValue($alpha);
1334
 
1335
		if ((is_numeric($trials)) && (is_numeric($probability)) && (is_numeric($alpha))) {
1336
			if ($trials < 0) {
1337
				return PHPExcel_Calculation_Functions::NaN();
1338
			}
1339
			if (($probability < 0) || ($probability > 1)) {
1340
				return PHPExcel_Calculation_Functions::NaN();
1341
			}
1342
			if (($alpha < 0) || ($alpha > 1)) {
1343
				return PHPExcel_Calculation_Functions::NaN();
1344
			}
1345
			if ($alpha <= 0.5) {
1346
				$t = sqrt(log(1 / ($alpha * $alpha)));
1347
				$trialsApprox = 0 - ($t + (2.515517 + 0.802853 * $t + 0.010328 * $t * $t) / (1 + 1.432788 * $t + 0.189269 * $t * $t + 0.001308 * $t * $t * $t));
1348
			} else {
1349
				$t = sqrt(log(1 / pow(1 - $alpha,2)));
1350
				$trialsApprox = $t - (2.515517 + 0.802853 * $t + 0.010328 * $t * $t) / (1 + 1.432788 * $t + 0.189269 * $t * $t + 0.001308 * $t * $t * $t);
1351
			}
1352
			$Guess = floor($trials * $probability + $trialsApprox * sqrt($trials * $probability * (1 - $probability)));
1353
			if ($Guess < 0) {
1354
				$Guess = 0;
1355
			} elseif ($Guess > $trials) {
1356
				$Guess = $trials;
1357
			}
1358
 
1359
			$TotalUnscaledProbability = $UnscaledPGuess = $UnscaledCumPGuess = 0.0;
1360
			$EssentiallyZero = 10e-12;
1361
 
1362
			$m = floor($trials * $probability);
1363
			++$TotalUnscaledProbability;
1364
			if ($m == $Guess) { ++$UnscaledPGuess; }
1365
			if ($m <= $Guess) { ++$UnscaledCumPGuess; }
1366
 
1367
			$PreviousValue = 1;
1368
			$Done = False;
1369
			$k = $m + 1;
1370
			while ((!$Done) && ($k <= $trials)) {
1371
				$CurrentValue = $PreviousValue * ($trials - $k + 1) * $probability / ($k * (1 - $probability));
1372
				$TotalUnscaledProbability += $CurrentValue;
1373
				if ($k == $Guess) { $UnscaledPGuess += $CurrentValue; }
1374
				if ($k <= $Guess) { $UnscaledCumPGuess += $CurrentValue; }
1375
				if ($CurrentValue <= $EssentiallyZero) { $Done = True; }
1376
				$PreviousValue = $CurrentValue;
1377
				++$k;
1378
			}
1379
 
1380
			$PreviousValue = 1;
1381
			$Done = False;
1382
			$k = $m - 1;
1383
			while ((!$Done) && ($k >= 0)) {
1384
				$CurrentValue = $PreviousValue * $k + 1 * (1 - $probability) / (($trials - $k) * $probability);
1385
				$TotalUnscaledProbability += $CurrentValue;
1386
				if ($k == $Guess) { $UnscaledPGuess += $CurrentValue; }
1387
				if ($k <= $Guess) { $UnscaledCumPGuess += $CurrentValue; }
1388
				if ($CurrentValue <= $EssentiallyZero) { $Done = True; }
1389
				$PreviousValue = $CurrentValue;
1390
				--$k;
1391
			}
1392
 
1393
			$PGuess = $UnscaledPGuess / $TotalUnscaledProbability;
1394
			$CumPGuess = $UnscaledCumPGuess / $TotalUnscaledProbability;
1395
 
1396
//			$CumPGuessMinus1 = $CumPGuess - $PGuess;
1397
			$CumPGuessMinus1 = $CumPGuess - 1;
1398
 
1399
			while (True) {
1400
				if (($CumPGuessMinus1 < $alpha) && ($CumPGuess >= $alpha)) {
1401
					return $Guess;
1402
				} elseif (($CumPGuessMinus1 < $alpha) && ($CumPGuess < $alpha)) {
1403
					$PGuessPlus1 = $PGuess * ($trials - $Guess) * $probability / $Guess / (1 - $probability);
1404
					$CumPGuessMinus1 = $CumPGuess;
1405
					$CumPGuess = $CumPGuess + $PGuessPlus1;
1406
					$PGuess = $PGuessPlus1;
1407
					++$Guess;
1408
				} elseif (($CumPGuessMinus1 >= $alpha) && ($CumPGuess >= $alpha)) {
1409
					$PGuessMinus1 = $PGuess * $Guess * (1 - $probability) / ($trials - $Guess + 1) / $probability;
1410
					$CumPGuess = $CumPGuessMinus1;
1411
					$CumPGuessMinus1 = $CumPGuessMinus1 - $PGuess;
1412
					$PGuess = $PGuessMinus1;
1413
					--$Guess;
1414
				}
1415
			}
1416
		}
1417
		return PHPExcel_Calculation_Functions::VALUE();
1418
	}	//	function CRITBINOM()
1419
 
1420
 
1421
	/**
1422
	 * DEVSQ
1423
	 *
1424
	 * Returns the sum of squares of deviations of data points from their sample mean.
1425
	 *
1426
	 * Excel Function:
1427
	 *		DEVSQ(value1[,value2[, ...]])
1428
	 *
1429
	 * @access	public
1430
	 * @category Statistical Functions
1431
	 * @param	mixed		$arg,...		Data values
1432
	 * @return	float
1433
	 */
1434
	public static function DEVSQ() {
1435
		$aArgs = PHPExcel_Calculation_Functions::flattenArrayIndexed(func_get_args());
1436
 
1437
		// Return value
1438
		$returnValue = null;
1439
 
1440
		$aMean = self::AVERAGE($aArgs);
1441
		if ($aMean != PHPExcel_Calculation_Functions::DIV0()) {
1442
			$aCount = -1;
1443
			foreach ($aArgs as $k => $arg) {
1444
				// Is it a numeric value?
1445
				if ((is_bool($arg)) &&
1446
					((!PHPExcel_Calculation_Functions::isCellValue($k)) || (PHPExcel_Calculation_Functions::getCompatibilityMode() == PHPExcel_Calculation_Functions::COMPATIBILITY_OPENOFFICE))) {
1447
					$arg = (integer) $arg;
1448
				}
1449
				if ((is_numeric($arg)) && (!is_string($arg))) {
1450
					if (is_null($returnValue)) {
1451
						$returnValue = pow(($arg - $aMean),2);
1452
					} else {
1453
						$returnValue += pow(($arg - $aMean),2);
1454
					}
1455
					++$aCount;
1456
				}
1457
			}
1458
 
1459
			// Return
1460
			if (is_null($returnValue)) {
1461
				return PHPExcel_Calculation_Functions::NaN();
1462
			} else {
1463
				return $returnValue;
1464
			}
1465
		}
1466
		return self::NA();
1467
	}	//	function DEVSQ()
1468
 
1469
 
1470
	/**
1471
	 * EXPONDIST
1472
	 *
1473
	 *	Returns the exponential distribution. Use EXPONDIST to model the time between events,
1474
	 *		such as how long an automated bank teller takes to deliver cash. For example, you can
1475
	 *		use EXPONDIST to determine the probability that the process takes at most 1 minute.
1476
	 *
1477
	 * @param	float		$value			Value of the function
1478
	 * @param	float		$lambda			The parameter value
1479
	 * @param	boolean		$cumulative
1480
	 * @return	float
1481
	 */
1482
	public static function EXPONDIST($value, $lambda, $cumulative) {
1483
		$value	= PHPExcel_Calculation_Functions::flattenSingleValue($value);
1484
		$lambda	= PHPExcel_Calculation_Functions::flattenSingleValue($lambda);
1485
		$cumulative	= PHPExcel_Calculation_Functions::flattenSingleValue($cumulative);
1486
 
1487
		if ((is_numeric($value)) && (is_numeric($lambda))) {
1488
			if (($value < 0) || ($lambda < 0)) {
1489
				return PHPExcel_Calculation_Functions::NaN();
1490
			}
1491
			if ((is_numeric($cumulative)) || (is_bool($cumulative))) {
1492
				if ($cumulative) {
1493
					return 1 - exp(0-$value*$lambda);
1494
				} else {
1495
					return $lambda * exp(0-$value*$lambda);
1496
				}
1497
			}
1498
		}
1499
		return PHPExcel_Calculation_Functions::VALUE();
1500
	}	//	function EXPONDIST()
1501
 
1502
 
1503
	/**
1504
	 * FISHER
1505
	 *
1506
	 * Returns the Fisher transformation at x. This transformation produces a function that
1507
	 *		is normally distributed rather than skewed. Use this function to perform hypothesis
1508
	 *		testing on the correlation coefficient.
1509
	 *
1510
	 * @param	float		$value
1511
	 * @return	float
1512
	 */
1513
	public static function FISHER($value) {
1514
		$value	= PHPExcel_Calculation_Functions::flattenSingleValue($value);
1515
 
1516
		if (is_numeric($value)) {
1517
			if (($value <= -1) || ($value >= 1)) {
1518
				return PHPExcel_Calculation_Functions::NaN();
1519
			}
1520
			return 0.5 * log((1+$value)/(1-$value));
1521
		}
1522
		return PHPExcel_Calculation_Functions::VALUE();
1523
	}	//	function FISHER()
1524
 
1525
 
1526
	/**
1527
	 * FISHERINV
1528
	 *
1529
	 * Returns the inverse of the Fisher transformation. Use this transformation when
1530
	 *		analyzing correlations between ranges or arrays of data. If y = FISHER(x), then
1531
	 *		FISHERINV(y) = x.
1532
	 *
1533
	 * @param	float		$value
1534
	 * @return	float
1535
	 */
1536
	public static function FISHERINV($value) {
1537
		$value	= PHPExcel_Calculation_Functions::flattenSingleValue($value);
1538
 
1539
		if (is_numeric($value)) {
1540
			return (exp(2 * $value) - 1) / (exp(2 * $value) + 1);
1541
		}
1542
		return PHPExcel_Calculation_Functions::VALUE();
1543
	}	//	function FISHERINV()
1544
 
1545
 
1546
	/**
1547
	 * FORECAST
1548
	 *
1549
	 * Calculates, or predicts, a future value by using existing values. The predicted value is a y-value for a given x-value.
1550
	 *
1551
	 * @param	float				Value of X for which we want to find Y
1552
	 * @param	array of mixed		Data Series Y
1553
	 * @param	array of mixed		Data Series X
1554
	 * @return	float
1555
	 */
1556
	public static function FORECAST($xValue,$yValues,$xValues) {
1557
		$xValue	= PHPExcel_Calculation_Functions::flattenSingleValue($xValue);
1558
		if (!is_numeric($xValue)) {
1559
			return PHPExcel_Calculation_Functions::VALUE();
1560
		}
1561
 
1562
		if (!self::_checkTrendArrays($yValues,$xValues)) {
1563
			return PHPExcel_Calculation_Functions::VALUE();
1564
		}
1565
		$yValueCount = count($yValues);
1566
		$xValueCount = count($xValues);
1567
 
1568
		if (($yValueCount == 0) || ($yValueCount != $xValueCount)) {
1569
			return PHPExcel_Calculation_Functions::NA();
1570
		} elseif ($yValueCount == 1) {
1571
			return PHPExcel_Calculation_Functions::DIV0();
1572
		}
1573
 
1574
		$bestFitLinear = trendClass::calculate(trendClass::TREND_LINEAR,$yValues,$xValues);
1575
		return $bestFitLinear->getValueOfYForX($xValue);
1576
	}	//	function FORECAST()
1577
 
1578
 
1579
	/**
1580
	 * GAMMADIST
1581
	 *
1582
	 * Returns the gamma distribution.
1583
	 *
1584
	 * @param	float		$value			Value at which you want to evaluate the distribution
1585
	 * @param	float		$a				Parameter to the distribution
1586
	 * @param	float		$b				Parameter to the distribution
1587
	 * @param	boolean		$cumulative
1588
	 * @return	float
1589
	 *
1590
	 */
1591
	public static function GAMMADIST($value,$a,$b,$cumulative) {
1592
		$value	= PHPExcel_Calculation_Functions::flattenSingleValue($value);
1593
		$a		= PHPExcel_Calculation_Functions::flattenSingleValue($a);
1594
		$b		= PHPExcel_Calculation_Functions::flattenSingleValue($b);
1595
 
1596
		if ((is_numeric($value)) && (is_numeric($a)) && (is_numeric($b))) {
1597
			if (($value < 0) || ($a <= 0) || ($b <= 0)) {
1598
				return PHPExcel_Calculation_Functions::NaN();
1599
			}
1600
			if ((is_numeric($cumulative)) || (is_bool($cumulative))) {
1601
				if ($cumulative) {
1602
					return self::_incompleteGamma($a,$value / $b) / self::_gamma($a);
1603
				} else {
1604
					return (1 / (pow($b,$a) * self::_gamma($a))) * pow($value,$a-1) * exp(0-($value / $b));
1605
				}
1606
			}
1607
		}
1608
		return PHPExcel_Calculation_Functions::VALUE();
1609
	}	//	function GAMMADIST()
1610
 
1611
 
1612
	/**
1613
	 * GAMMAINV
1614
	 *
1615
	 * Returns the inverse of the beta distribution.
1616
	 *
1617
	 * @param	float		$probability	Probability at which you want to evaluate the distribution
1618
	 * @param	float		$alpha			Parameter to the distribution
1619
	 * @param	float		$beta			Parameter to the distribution
1620
	 * @return	float
1621
	 *
1622
	 */
1623
	public static function GAMMAINV($probability,$alpha,$beta) {
1624
		$probability	= PHPExcel_Calculation_Functions::flattenSingleValue($probability);
1625
		$alpha			= PHPExcel_Calculation_Functions::flattenSingleValue($alpha);
1626
		$beta			= PHPExcel_Calculation_Functions::flattenSingleValue($beta);
1627
 
1628
		if ((is_numeric($probability)) && (is_numeric($alpha)) && (is_numeric($beta))) {
1629
			if (($alpha <= 0) || ($beta <= 0) || ($probability < 0) || ($probability > 1)) {
1630
				return PHPExcel_Calculation_Functions::NaN();
1631
			}
1632
 
1633
			$xLo = 0;
1634
			$xHi = $alpha * $beta * 5;
1635
 
1636
			$x = $xNew = 1;
1637
			$error = $pdf = 0;
1638
			$dx	= 1024;
1639
			$i = 0;
1640
 
1641
			while ((abs($dx) > PRECISION) && ($i++ < MAX_ITERATIONS)) {
1642
				// Apply Newton-Raphson step
1643
				$error = self::GAMMADIST($x, $alpha, $beta, True) - $probability;
1644
				if ($error < 0.0) {
1645
					$xLo = $x;
1646
				} else {
1647
					$xHi = $x;
1648
				}
1649
				$pdf = self::GAMMADIST($x, $alpha, $beta, False);
1650
				// Avoid division by zero
1651
				if ($pdf != 0.0) {
1652
					$dx = $error / $pdf;
1653
					$xNew = $x - $dx;
1654
				}
1655
				// If the NR fails to converge (which for example may be the
1656
				// case if the initial guess is too rough) we apply a bisection
1657
				// step to determine a more narrow interval around the root.
1658
				if (($xNew < $xLo) || ($xNew > $xHi) || ($pdf == 0.0)) {
1659
					$xNew = ($xLo + $xHi) / 2;
1660
					$dx = $xNew - $x;
1661
				}
1662
				$x = $xNew;
1663
			}
1664
			if ($i == MAX_ITERATIONS) {
1665
				return PHPExcel_Calculation_Functions::NA();
1666
			}
1667
			return $x;
1668
		}
1669
		return PHPExcel_Calculation_Functions::VALUE();
1670
	}	//	function GAMMAINV()
1671
 
1672
 
1673
	/**
1674
	 * GAMMALN
1675
	 *
1676
	 * Returns the natural logarithm of the gamma function.
1677
	 *
1678
	 * @param	float		$value
1679
	 * @return	float
1680
	 */
1681
	public static function GAMMALN($value) {
1682
		$value	= PHPExcel_Calculation_Functions::flattenSingleValue($value);
1683
 
1684
		if (is_numeric($value)) {
1685
			if ($value <= 0) {
1686
				return PHPExcel_Calculation_Functions::NaN();
1687
			}
1688
			return log(self::_gamma($value));
1689
		}
1690
		return PHPExcel_Calculation_Functions::VALUE();
1691
	}	//	function GAMMALN()
1692
 
1693
 
1694
	/**
1695
	 * GEOMEAN
1696
	 *
1697
	 * Returns the geometric mean of an array or range of positive data. For example, you
1698
	 *		can use GEOMEAN to calculate average growth rate given compound interest with
1699
	 *		variable rates.
1700
	 *
1701
	 * Excel Function:
1702
	 *		GEOMEAN(value1[,value2[, ...]])
1703
	 *
1704
	 * @access	public
1705
	 * @category Statistical Functions
1706
	 * @param	mixed		$arg,...		Data values
1707
	 * @return	float
1708
	 */
1709
	public static function GEOMEAN() {
1710
		$aArgs = PHPExcel_Calculation_Functions::flattenArray(func_get_args());
1711
 
1712
		$aMean = PHPExcel_Calculation_MathTrig::PRODUCT($aArgs);
1713
		if (is_numeric($aMean) && ($aMean > 0)) {
1714
			$aCount = self::COUNT($aArgs) ;
1715
			if (self::MIN($aArgs) > 0) {
1716
				return pow($aMean, (1 / $aCount));
1717
			}
1718
		}
1719
		return PHPExcel_Calculation_Functions::NaN();
1720
	}	//	GEOMEAN()
1721
 
1722
 
1723
	/**
1724
	 * GROWTH
1725
	 *
1726
	 * Returns values along a predicted emponential trend
1727
	 *
1728
	 * @param	array of mixed		Data Series Y
1729
	 * @param	array of mixed		Data Series X
1730
	 * @param	array of mixed		Values of X for which we want to find Y
1731
	 * @param	boolean				A logical value specifying whether to force the intersect to equal 0.
1732
	 * @return	array of float
1733
	 */
1734
	public static function GROWTH($yValues,$xValues=array(),$newValues=array(),$const=True) {
1735
		$yValues = PHPExcel_Calculation_Functions::flattenArray($yValues);
1736
		$xValues = PHPExcel_Calculation_Functions::flattenArray($xValues);
1737
		$newValues = PHPExcel_Calculation_Functions::flattenArray($newValues);
1738
		$const	= (is_null($const))	? True :	(boolean) PHPExcel_Calculation_Functions::flattenSingleValue($const);
1739
 
1740
		$bestFitExponential = trendClass::calculate(trendClass::TREND_EXPONENTIAL,$yValues,$xValues,$const);
1741
		if (empty($newValues)) {
1742
			$newValues = $bestFitExponential->getXValues();
1743
		}
1744
 
1745
		$returnArray = array();
1746
		foreach($newValues as $xValue) {
1747
			$returnArray[0][] = $bestFitExponential->getValueOfYForX($xValue);
1748
		}
1749
 
1750
		return $returnArray;
1751
	}	//	function GROWTH()
1752
 
1753
 
1754
	/**
1755
	 * HARMEAN
1756
	 *
1757
	 * Returns the harmonic mean of a data set. The harmonic mean is the reciprocal of the
1758
	 *		arithmetic mean of reciprocals.
1759
	 *
1760
	 * Excel Function:
1761
	 *		HARMEAN(value1[,value2[, ...]])
1762
	 *
1763
	 * @access	public
1764
	 * @category Statistical Functions
1765
	 * @param	mixed		$arg,...		Data values
1766
	 * @return	float
1767
	 */
1768
	public static function HARMEAN() {
1769
		// Return value
1770
		$returnValue = PHPExcel_Calculation_Functions::NA();
1771
 
1772
		// Loop through arguments
1773
		$aArgs = PHPExcel_Calculation_Functions::flattenArray(func_get_args());
1774
		if (self::MIN($aArgs) < 0) {
1775
			return PHPExcel_Calculation_Functions::NaN();
1776
		}
1777
		$aCount = 0;
1778
		foreach ($aArgs as $arg) {
1779
			// Is it a numeric value?
1780
			if ((is_numeric($arg)) && (!is_string($arg))) {
1781
				if ($arg <= 0) {
1782
					return PHPExcel_Calculation_Functions::NaN();
1783
				}
1784
				if (is_null($returnValue)) {
1785
					$returnValue = (1 / $arg);
1786
				} else {
1787
					$returnValue += (1 / $arg);
1788
				}
1789
				++$aCount;
1790
			}
1791
		}
1792
 
1793
		// Return
1794
		if ($aCount > 0) {
1795
			return 1 / ($returnValue / $aCount);
1796
		} else {
1797
			return $returnValue;
1798
		}
1799
	}	//	function HARMEAN()
1800
 
1801
 
1802
	/**
1803
	 * HYPGEOMDIST
1804
	 *
1805
	 * Returns the hypergeometric distribution. HYPGEOMDIST returns the probability of a given number of
1806
	 * sample successes, given the sample size, population successes, and population size.
1807
	 *
1808
	 * @param	float		$sampleSuccesses		Number of successes in the sample
1809
	 * @param	float		$sampleNumber			Size of the sample
1810
	 * @param	float		$populationSuccesses	Number of successes in the population
1811
	 * @param	float		$populationNumber		Population size
1812
	 * @return	float
1813
	 *
1814
	 */
1815
	public static function HYPGEOMDIST($sampleSuccesses, $sampleNumber, $populationSuccesses, $populationNumber) {
1816
		$sampleSuccesses		= floor(PHPExcel_Calculation_Functions::flattenSingleValue($sampleSuccesses));
1817
		$sampleNumber			= floor(PHPExcel_Calculation_Functions::flattenSingleValue($sampleNumber));
1818
		$populationSuccesses	= floor(PHPExcel_Calculation_Functions::flattenSingleValue($populationSuccesses));
1819
		$populationNumber		= floor(PHPExcel_Calculation_Functions::flattenSingleValue($populationNumber));
1820
 
1821
		if ((is_numeric($sampleSuccesses)) && (is_numeric($sampleNumber)) && (is_numeric($populationSuccesses)) && (is_numeric($populationNumber))) {
1822
			if (($sampleSuccesses < 0) || ($sampleSuccesses > $sampleNumber) || ($sampleSuccesses > $populationSuccesses)) {
1823
				return PHPExcel_Calculation_Functions::NaN();
1824
			}
1825
			if (($sampleNumber <= 0) || ($sampleNumber > $populationNumber)) {
1826
				return PHPExcel_Calculation_Functions::NaN();
1827
			}
1828
			if (($populationSuccesses <= 0) || ($populationSuccesses > $populationNumber)) {
1829
				return PHPExcel_Calculation_Functions::NaN();
1830
			}
1831
			return PHPExcel_Calculation_MathTrig::COMBIN($populationSuccesses,$sampleSuccesses) *
1832
				   PHPExcel_Calculation_MathTrig::COMBIN($populationNumber - $populationSuccesses,$sampleNumber - $sampleSuccesses) /
1833
				   PHPExcel_Calculation_MathTrig::COMBIN($populationNumber,$sampleNumber);
1834
		}
1835
		return PHPExcel_Calculation_Functions::VALUE();
1836
	}	//	function HYPGEOMDIST()
1837
 
1838
 
1839
	/**
1840
	 * INTERCEPT
1841
	 *
1842
	 * Calculates the point at which a line will intersect the y-axis by using existing x-values and y-values.
1843
	 *
1844
	 * @param	array of mixed		Data Series Y
1845
	 * @param	array of mixed		Data Series X
1846
	 * @return	float
1847
	 */
1848
	public static function INTERCEPT($yValues,$xValues) {
1849
		if (!self::_checkTrendArrays($yValues,$xValues)) {
1850
			return PHPExcel_Calculation_Functions::VALUE();
1851
		}
1852
		$yValueCount = count($yValues);
1853
		$xValueCount = count($xValues);
1854
 
1855
		if (($yValueCount == 0) || ($yValueCount != $xValueCount)) {
1856
			return PHPExcel_Calculation_Functions::NA();
1857
		} elseif ($yValueCount == 1) {
1858
			return PHPExcel_Calculation_Functions::DIV0();
1859
		}
1860
 
1861
		$bestFitLinear = trendClass::calculate(trendClass::TREND_LINEAR,$yValues,$xValues);
1862
		return $bestFitLinear->getIntersect();
1863
	}	//	function INTERCEPT()
1864
 
1865
 
1866
	/**
1867
	 * KURT
1868
	 *
1869
	 * Returns the kurtosis of a data set. Kurtosis characterizes the relative peakedness
1870
	 * or flatness of a distribution compared with the normal distribution. Positive
1871
	 * kurtosis indicates a relatively peaked distribution. Negative kurtosis indicates a
1872
	 * relatively flat distribution.
1873
	 *
1874
	 * @param	array	Data Series
1875
	 * @return	float
1876
	 */
1877
	public static function KURT() {
1878
		$aArgs = PHPExcel_Calculation_Functions::flattenArrayIndexed(func_get_args());
1879
		$mean = self::AVERAGE($aArgs);
1880
		$stdDev = self::STDEV($aArgs);
1881
 
1882
		if ($stdDev > 0) {
1883
			$count = $summer = 0;
1884
			// Loop through arguments
1885
			foreach ($aArgs as $k => $arg) {
1886
				if ((is_bool($arg)) &&
1887
					(!PHPExcel_Calculation_Functions::isMatrixValue($k))) {
1888
				} else {
1889
					// Is it a numeric value?
1890
					if ((is_numeric($arg)) && (!is_string($arg))) {
1891
						$summer += pow((($arg - $mean) / $stdDev),4) ;
1892
						++$count;
1893
					}
1894
				}
1895
			}
1896
 
1897
			// Return
1898
			if ($count > 3) {
1899
				return $summer * ($count * ($count+1) / (($count-1) * ($count-2) * ($count-3))) - (3 * pow($count-1,2) / (($count-2) * ($count-3)));
1900
			}
1901
		}
1902
		return PHPExcel_Calculation_Functions::DIV0();
1903
	}	//	function KURT()
1904
 
1905
 
1906
	/**
1907
	 * LARGE
1908
	 *
1909
	 * Returns the nth largest value in a data set. You can use this function to
1910
	 *		select a value based on its relative standing.
1911
	 *
1912
	 * Excel Function:
1913
	 *		LARGE(value1[,value2[, ...]],entry)
1914
	 *
1915
	 * @access	public
1916
	 * @category Statistical Functions
1917
	 * @param	mixed		$arg,...		Data values
1918
	 * @param	int			$entry			Position (ordered from the largest) in the array or range of data to return
1919
	 * @return	float
1920
	 *
1921
	 */
1922
	public static function LARGE() {
1923
		$aArgs = PHPExcel_Calculation_Functions::flattenArray(func_get_args());
1924
 
1925
		// Calculate
1926
		$entry = floor(array_pop($aArgs));
1927
 
1928
		if ((is_numeric($entry)) && (!is_string($entry))) {
1929
			$mArgs = array();
1930
			foreach ($aArgs as $arg) {
1931
				// Is it a numeric value?
1932
				if ((is_numeric($arg)) && (!is_string($arg))) {
1933
					$mArgs[] = $arg;
1934
				}
1935
			}
1936
			$count = self::COUNT($mArgs);
1937
			$entry = floor(--$entry);
1938
			if (($entry < 0) || ($entry >= $count) || ($count == 0)) {
1939
				return PHPExcel_Calculation_Functions::NaN();
1940
			}
1941
			rsort($mArgs);
1942
			return $mArgs[$entry];
1943
		}
1944
		return PHPExcel_Calculation_Functions::VALUE();
1945
	}	//	function LARGE()
1946
 
1947
 
1948
	/**
1949
	 * LINEST
1950
	 *
1951
	 * Calculates the statistics for a line by using the "least squares" method to calculate a straight line that best fits your data,
1952
	 *		and then returns an array that describes the line.
1953
	 *
1954
	 * @param	array of mixed		Data Series Y
1955
	 * @param	array of mixed		Data Series X
1956
	 * @param	boolean				A logical value specifying whether to force the intersect to equal 0.
1957
	 * @param	boolean				A logical value specifying whether to return additional regression statistics.
1958
	 * @return	array
1959
	 */
1960
	public static function LINEST($yValues, $xValues = NULL, $const = TRUE, $stats = FALSE) {
1961
		$const	= (is_null($const))	? TRUE :	(boolean) PHPExcel_Calculation_Functions::flattenSingleValue($const);
1962
		$stats	= (is_null($stats))	? FALSE :	(boolean) PHPExcel_Calculation_Functions::flattenSingleValue($stats);
1963
		if (is_null($xValues)) $xValues = range(1,count(PHPExcel_Calculation_Functions::flattenArray($yValues)));
1964
 
1965
		if (!self::_checkTrendArrays($yValues,$xValues)) {
1966
			return PHPExcel_Calculation_Functions::VALUE();
1967
		}
1968
		$yValueCount = count($yValues);
1969
		$xValueCount = count($xValues);
1970
 
1971
 
1972
		if (($yValueCount == 0) || ($yValueCount != $xValueCount)) {
1973
			return PHPExcel_Calculation_Functions::NA();
1974
		} elseif ($yValueCount == 1) {
1975
			return 0;
1976
		}
1977
 
1978
		$bestFitLinear = trendClass::calculate(trendClass::TREND_LINEAR,$yValues,$xValues,$const);
1979
		if ($stats) {
1980
			return array( array( $bestFitLinear->getSlope(),
1981
						 		 $bestFitLinear->getSlopeSE(),
1982
						 		 $bestFitLinear->getGoodnessOfFit(),
1983
						 		 $bestFitLinear->getF(),
1984
						 		 $bestFitLinear->getSSRegression(),
1985
							   ),
1986
						  array( $bestFitLinear->getIntersect(),
1987
								 $bestFitLinear->getIntersectSE(),
1988
								 $bestFitLinear->getStdevOfResiduals(),
1989
								 $bestFitLinear->getDFResiduals(),
1990
								 $bestFitLinear->getSSResiduals()
1991
							   )
1992
						);
1993
		} else {
1994
			return array( $bestFitLinear->getSlope(),
1995
						  $bestFitLinear->getIntersect()
1996
						);
1997
		}
1998
	}	//	function LINEST()
1999
 
2000
 
2001
	/**
2002
	 * LOGEST
2003
	 *
2004
	 * Calculates an exponential curve that best fits the X and Y data series,
2005
	 *		and then returns an array that describes the line.
2006
	 *
2007
	 * @param	array of mixed		Data Series Y
2008
	 * @param	array of mixed		Data Series X
2009
	 * @param	boolean				A logical value specifying whether to force the intersect to equal 0.
2010
	 * @param	boolean				A logical value specifying whether to return additional regression statistics.
2011
	 * @return	array
2012
	 */
2013
	public static function LOGEST($yValues,$xValues=null,$const=True,$stats=False) {
2014
		$const	= (is_null($const))	? True :	(boolean) PHPExcel_Calculation_Functions::flattenSingleValue($const);
2015
		$stats	= (is_null($stats))	? False :	(boolean) PHPExcel_Calculation_Functions::flattenSingleValue($stats);
2016
		if (is_null($xValues)) $xValues = range(1,count(PHPExcel_Calculation_Functions::flattenArray($yValues)));
2017
 
2018
		if (!self::_checkTrendArrays($yValues,$xValues)) {
2019
			return PHPExcel_Calculation_Functions::VALUE();
2020
		}
2021
		$yValueCount = count($yValues);
2022
		$xValueCount = count($xValues);
2023
 
2024
		foreach($yValues as $value) {
2025
			if ($value <= 0.0) {
2026
				return PHPExcel_Calculation_Functions::NaN();
2027
			}
2028
		}
2029
 
2030
 
2031
		if (($yValueCount == 0) || ($yValueCount != $xValueCount)) {
2032
			return PHPExcel_Calculation_Functions::NA();
2033
		} elseif ($yValueCount == 1) {
2034
			return 1;
2035
		}
2036
 
2037
		$bestFitExponential = trendClass::calculate(trendClass::TREND_EXPONENTIAL,$yValues,$xValues,$const);
2038
		if ($stats) {
2039
			return array( array( $bestFitExponential->getSlope(),
2040
						 		 $bestFitExponential->getSlopeSE(),
2041
						 		 $bestFitExponential->getGoodnessOfFit(),
2042
						 		 $bestFitExponential->getF(),
2043
						 		 $bestFitExponential->getSSRegression(),
2044
							   ),
2045
						  array( $bestFitExponential->getIntersect(),
2046
								 $bestFitExponential->getIntersectSE(),
2047
								 $bestFitExponential->getStdevOfResiduals(),
2048
								 $bestFitExponential->getDFResiduals(),
2049
								 $bestFitExponential->getSSResiduals()
2050
							   )
2051
						);
2052
		} else {
2053
			return array( $bestFitExponential->getSlope(),
2054
						  $bestFitExponential->getIntersect()
2055
						);
2056
		}
2057
	}	//	function LOGEST()
2058
 
2059
 
2060
	/**
2061
	 * LOGINV
2062
	 *
2063
	 * Returns the inverse of the normal cumulative distribution
2064
	 *
2065
	 * @param	float		$probability
2066
	 * @param	float		$mean
2067
	 * @param	float		$stdDev
2068
	 * @return	float
2069
	 *
2070
	 * @todo	Try implementing P J Acklam's refinement algorithm for greater
2071
	 *			accuracy if I can get my head round the mathematics
2072
	 *			(as described at) http://home.online.no/~pjacklam/notes/invnorm/
2073
	 */
2074
	public static function LOGINV($probability, $mean, $stdDev) {
2075
		$probability	= PHPExcel_Calculation_Functions::flattenSingleValue($probability);
2076
		$mean			= PHPExcel_Calculation_Functions::flattenSingleValue($mean);
2077
		$stdDev			= PHPExcel_Calculation_Functions::flattenSingleValue($stdDev);
2078
 
2079
		if ((is_numeric($probability)) && (is_numeric($mean)) && (is_numeric($stdDev))) {
2080
			if (($probability < 0) || ($probability > 1) || ($stdDev <= 0)) {
2081
				return PHPExcel_Calculation_Functions::NaN();
2082
			}
2083
			return exp($mean + $stdDev * self::NORMSINV($probability));
2084
		}
2085
		return PHPExcel_Calculation_Functions::VALUE();
2086
	}	//	function LOGINV()
2087
 
2088
 
2089
	/**
2090
	 * LOGNORMDIST
2091
	 *
2092
	 * Returns the cumulative lognormal distribution of x, where ln(x) is normally distributed
2093
	 * with parameters mean and standard_dev.
2094
	 *
2095
	 * @param	float		$value
2096
	 * @param	float		$mean
2097
	 * @param	float		$stdDev
2098
	 * @return	float
2099
	 */
2100
	public static function LOGNORMDIST($value, $mean, $stdDev) {
2101
		$value	= PHPExcel_Calculation_Functions::flattenSingleValue($value);
2102
		$mean	= PHPExcel_Calculation_Functions::flattenSingleValue($mean);
2103
		$stdDev	= PHPExcel_Calculation_Functions::flattenSingleValue($stdDev);
2104
 
2105
		if ((is_numeric($value)) && (is_numeric($mean)) && (is_numeric($stdDev))) {
2106
			if (($value <= 0) || ($stdDev <= 0)) {
2107
				return PHPExcel_Calculation_Functions::NaN();
2108
			}
2109
			return self::NORMSDIST((log($value) - $mean) / $stdDev);
2110
		}
2111
		return PHPExcel_Calculation_Functions::VALUE();
2112
	}	//	function LOGNORMDIST()
2113
 
2114
 
2115
	/**
2116
	 * MAX
2117
	 *
2118
	 * MAX returns the value of the element of the values passed that has the highest value,
2119
	 *		with negative numbers considered smaller than positive numbers.
2120
	 *
2121
	 * Excel Function:
2122
	 *		MAX(value1[,value2[, ...]])
2123
	 *
2124
	 * @access	public
2125
	 * @category Statistical Functions
2126
	 * @param	mixed		$arg,...		Data values
2127
	 * @return	float
2128
	 */
2129
	public static function MAX() {
2130
		// Return value
2131
		$returnValue = null;
2132
 
2133
		// Loop through arguments
2134
		$aArgs = PHPExcel_Calculation_Functions::flattenArray(func_get_args());
2135
		foreach ($aArgs as $arg) {
2136
			// Is it a numeric value?
2137
			if ((is_numeric($arg)) && (!is_string($arg))) {
2138
				if ((is_null($returnValue)) || ($arg > $returnValue)) {
2139
					$returnValue = $arg;
2140
				}
2141
			}
2142
		}
2143
 
2144
		// Return
2145
		if(is_null($returnValue)) {
2146
			return 0;
2147
		}
2148
		return $returnValue;
2149
	}	//	function MAX()
2150
 
2151
 
2152
	/**
2153
	 * MAXA
2154
	 *
2155
	 * Returns the greatest value in a list of arguments, including numbers, text, and logical values
2156
	 *
2157
	 * Excel Function:
2158
	 *		MAXA(value1[,value2[, ...]])
2159
	 *
2160
	 * @access	public
2161
	 * @category Statistical Functions
2162
	 * @param	mixed		$arg,...		Data values
2163
	 * @return	float
2164
	 */
2165
	public static function MAXA() {
2166
		// Return value
2167
		$returnValue = null;
2168
 
2169
		// Loop through arguments
2170
		$aArgs = PHPExcel_Calculation_Functions::flattenArray(func_get_args());
2171
		foreach ($aArgs as $arg) {
2172
			// Is it a numeric value?
2173
			if ((is_numeric($arg)) || (is_bool($arg)) || ((is_string($arg) && ($arg != '')))) {
2174
				if (is_bool($arg)) {
2175
					$arg = (integer) $arg;
2176
				} elseif (is_string($arg)) {
2177
					$arg = 0;
2178
				}
2179
				if ((is_null($returnValue)) || ($arg > $returnValue)) {
2180
					$returnValue = $arg;
2181
				}
2182
			}
2183
		}
2184
 
2185
		// Return
2186
		if(is_null($returnValue)) {
2187
			return 0;
2188
		}
2189
		return $returnValue;
2190
	}	//	function MAXA()
2191
 
2192
 
2193
	/**
2194
	 * MAXIF
2195
	 *
2196
	 * Counts the maximum value within a range of cells that contain numbers within the list of arguments
2197
	 *
2198
	 * Excel Function:
2199
	 *		MAXIF(value1[,value2[, ...]],condition)
2200
	 *
2201
	 * @access	public
2202
	 * @category Mathematical and Trigonometric Functions
2203
	 * @param	mixed		$arg,...		Data values
2204
	 * @param	string		$condition		The criteria that defines which cells will be checked.
2205
	 * @return	float
2206
	 */
2207
	public static function MAXIF($aArgs,$condition,$sumArgs = array()) {
2208
		// Return value
2209
		$returnValue = null;
2210
 
2211
		$aArgs = PHPExcel_Calculation_Functions::flattenArray($aArgs);
2212
		$sumArgs = PHPExcel_Calculation_Functions::flattenArray($sumArgs);
2213
		if (empty($sumArgs)) {
2214
			$sumArgs = $aArgs;
2215
		}
2216
		$condition = PHPExcel_Calculation_Functions::_ifCondition($condition);
2217
		// Loop through arguments
2218
		foreach ($aArgs as $key => $arg) {
2219
			if (!is_numeric($arg)) { $arg = PHPExcel_Calculation::_wrapResult(strtoupper($arg)); }
2220
			$testCondition = '='.$arg.$condition;
2221
			if (PHPExcel_Calculation::getInstance()->_calculateFormulaValue($testCondition)) {
2222
				if ((is_null($returnValue)) || ($arg > $returnValue)) {
2223
					$returnValue = $arg;
2224
				}
2225
			}
2226
		}
2227
 
2228
		// Return
2229
		return $returnValue;
2230
	}	//	function MAXIF()
2231
 
2232
 
2233
	/**
2234
	 * MEDIAN
2235
	 *
2236
	 * Returns the median of the given numbers. The median is the number in the middle of a set of numbers.
2237
	 *
2238
	 * Excel Function:
2239
	 *		MEDIAN(value1[,value2[, ...]])
2240
	 *
2241
	 * @access	public
2242
	 * @category Statistical Functions
2243
	 * @param	mixed		$arg,...		Data values
2244
	 * @return	float
2245
	 */
2246
	public static function MEDIAN() {
2247
		// Return value
2248
		$returnValue = PHPExcel_Calculation_Functions::NaN();
2249
 
2250
		$mArgs = array();
2251
		// Loop through arguments
2252
		$aArgs = PHPExcel_Calculation_Functions::flattenArray(func_get_args());
2253
		foreach ($aArgs as $arg) {
2254
			// Is it a numeric value?
2255
			if ((is_numeric($arg)) && (!is_string($arg))) {
2256
				$mArgs[] = $arg;
2257
			}
2258
		}
2259
 
2260
		$mValueCount = count($mArgs);
2261
		if ($mValueCount > 0) {
2262
			sort($mArgs,SORT_NUMERIC);
2263
			$mValueCount = $mValueCount / 2;
2264
			if ($mValueCount == floor($mValueCount)) {
2265
				$returnValue = ($mArgs[$mValueCount--] + $mArgs[$mValueCount]) / 2;
2266
			} else {
2267
				$mValueCount == floor($mValueCount);
2268
				$returnValue = $mArgs[$mValueCount];
2269
			}
2270
		}
2271
 
2272
		// Return
2273
		return $returnValue;
2274
	}	//	function MEDIAN()
2275
 
2276
 
2277
	/**
2278
	 * MIN
2279
	 *
2280
	 * MIN returns the value of the element of the values passed that has the smallest value,
2281
	 *		with negative numbers considered smaller than positive numbers.
2282
	 *
2283
	 * Excel Function:
2284
	 *		MIN(value1[,value2[, ...]])
2285
	 *
2286
	 * @access	public
2287
	 * @category Statistical Functions
2288
	 * @param	mixed		$arg,...		Data values
2289
	 * @return	float
2290
	 */
2291
	public static function MIN() {
2292
		// Return value
2293
		$returnValue = null;
2294
 
2295
		// Loop through arguments
2296
		$aArgs = PHPExcel_Calculation_Functions::flattenArray(func_get_args());
2297
		foreach ($aArgs as $arg) {
2298
			// Is it a numeric value?
2299
			if ((is_numeric($arg)) && (!is_string($arg))) {
2300
				if ((is_null($returnValue)) || ($arg < $returnValue)) {
2301
					$returnValue = $arg;
2302
				}
2303
			}
2304
		}
2305
 
2306
		// Return
2307
		if(is_null($returnValue)) {
2308
			return 0;
2309
		}
2310
		return $returnValue;
2311
	}	//	function MIN()
2312
 
2313
 
2314
	/**
2315
	 * MINA
2316
	 *
2317
	 * Returns the smallest value in a list of arguments, including numbers, text, and logical values
2318
	 *
2319
	 * Excel Function:
2320
	 *		MINA(value1[,value2[, ...]])
2321
	 *
2322
	 * @access	public
2323
	 * @category Statistical Functions
2324
	 * @param	mixed		$arg,...		Data values
2325
	 * @return	float
2326
	 */
2327
	public static function MINA() {
2328
		// Return value
2329
		$returnValue = null;
2330
 
2331
		// Loop through arguments
2332
		$aArgs = PHPExcel_Calculation_Functions::flattenArray(func_get_args());
2333
		foreach ($aArgs as $arg) {
2334
			// Is it a numeric value?
2335
			if ((is_numeric($arg)) || (is_bool($arg)) || ((is_string($arg) && ($arg != '')))) {
2336
				if (is_bool($arg)) {
2337
					$arg = (integer) $arg;
2338
				} elseif (is_string($arg)) {
2339
					$arg = 0;
2340
				}
2341
				if ((is_null($returnValue)) || ($arg < $returnValue)) {
2342
					$returnValue = $arg;
2343
				}
2344
			}
2345
		}
2346
 
2347
		// Return
2348
		if(is_null($returnValue)) {
2349
			return 0;
2350
		}
2351
		return $returnValue;
2352
	}	//	function MINA()
2353
 
2354
 
2355
	/**
2356
	 * MINIF
2357
	 *
2358
	 * Returns the minimum value within a range of cells that contain numbers within the list of arguments
2359
	 *
2360
	 * Excel Function:
2361
	 *		MINIF(value1[,value2[, ...]],condition)
2362
	 *
2363
	 * @access	public
2364
	 * @category Mathematical and Trigonometric Functions
2365
	 * @param	mixed		$arg,...		Data values
2366
	 * @param	string		$condition		The criteria that defines which cells will be checked.
2367
	 * @return	float
2368
	 */
2369
	public static function MINIF($aArgs,$condition,$sumArgs = array()) {
2370
		// Return value
2371
		$returnValue = null;
2372
 
2373
		$aArgs = PHPExcel_Calculation_Functions::flattenArray($aArgs);
2374
		$sumArgs = PHPExcel_Calculation_Functions::flattenArray($sumArgs);
2375
		if (empty($sumArgs)) {
2376
			$sumArgs = $aArgs;
2377
		}
2378
		$condition = PHPExcel_Calculation_Functions::_ifCondition($condition);
2379
		// Loop through arguments
2380
		foreach ($aArgs as $key => $arg) {
2381
			if (!is_numeric($arg)) { $arg = PHPExcel_Calculation::_wrapResult(strtoupper($arg)); }
2382
			$testCondition = '='.$arg.$condition;
2383
			if (PHPExcel_Calculation::getInstance()->_calculateFormulaValue($testCondition)) {
2384
				if ((is_null($returnValue)) || ($arg < $returnValue)) {
2385
					$returnValue = $arg;
2386
				}
2387
			}
2388
		}
2389
 
2390
		// Return
2391
		return $returnValue;
2392
	}	//	function MINIF()
2393
 
2394
 
2395
	//
2396
	//	Special variant of array_count_values that isn't limited to strings and integers,
2397
	//		but can work with floating point numbers as values
2398
	//
2399
	private static function _modeCalc($data) {
2400
		$frequencyArray = array();
2401
		foreach($data as $datum) {
2402
			$found = False;
2403
			foreach($frequencyArray as $key => $value) {
2404
				if ((string) $value['value'] == (string) $datum) {
2405
					++$frequencyArray[$key]['frequency'];
2406
					$found = True;
2407
					break;
2408
				}
2409
			}
2410
			if (!$found) {
2411
				$frequencyArray[] = array('value'		=> $datum,
2412
										  'frequency'	=>	1 );
2413
			}
2414
		}
2415
 
2416
		foreach($frequencyArray as $key => $value) {
2417
			$frequencyList[$key] = $value['frequency'];
2418
			$valueList[$key] = $value['value'];
2419
		}
2420
		array_multisort($frequencyList, SORT_DESC, $valueList, SORT_ASC, SORT_NUMERIC, $frequencyArray);
2421
 
2422
		if ($frequencyArray[0]['frequency'] == 1) {
2423
			return PHPExcel_Calculation_Functions::NA();
2424
		}
2425
		return $frequencyArray[0]['value'];
2426
	}	//	function _modeCalc()
2427
 
2428
 
2429
	/**
2430
	 * MODE
2431
	 *
2432
	 * Returns the most frequently occurring, or repetitive, value in an array or range of data
2433
	 *
2434
	 * Excel Function:
2435
	 *		MODE(value1[,value2[, ...]])
2436
	 *
2437
	 * @access	public
2438
	 * @category Statistical Functions
2439
	 * @param	mixed		$arg,...		Data values
2440
	 * @return	float
2441
	 */
2442
	public static function MODE() {
2443
		// Return value
2444
		$returnValue = PHPExcel_Calculation_Functions::NA();
2445
 
2446
		// Loop through arguments
2447
		$aArgs = PHPExcel_Calculation_Functions::flattenArray(func_get_args());
2448
 
2449
		$mArgs = array();
2450
		foreach ($aArgs as $arg) {
2451
			// Is it a numeric value?
2452
			if ((is_numeric($arg)) && (!is_string($arg))) {
2453
				$mArgs[] = $arg;
2454
			}
2455
		}
2456
 
2457
		if (!empty($mArgs)) {
2458
			return self::_modeCalc($mArgs);
2459
		}
2460
 
2461
		// Return
2462
		return $returnValue;
2463
	}	//	function MODE()
2464
 
2465
 
2466
	/**
2467
	 * NEGBINOMDIST
2468
	 *
2469
	 * Returns the negative binomial distribution. NEGBINOMDIST returns the probability that
2470
	 *		there will be number_f failures before the number_s-th success, when the constant
2471
	 *		probability of a success is probability_s. This function is similar to the binomial
2472
	 *		distribution, except that the number of successes is fixed, and the number of trials is
2473
	 *		variable. Like the binomial, trials are assumed to be independent.
2474
	 *
2475
	 * @param	float		$failures		Number of Failures
2476
	 * @param	float		$successes		Threshold number of Successes
2477
	 * @param	float		$probability	Probability of success on each trial
2478
	 * @return	float
2479
	 *
2480
	 */
2481
	public static function NEGBINOMDIST($failures, $successes, $probability) {
2482
		$failures		= floor(PHPExcel_Calculation_Functions::flattenSingleValue($failures));
2483
		$successes		= floor(PHPExcel_Calculation_Functions::flattenSingleValue($successes));
2484
		$probability	= PHPExcel_Calculation_Functions::flattenSingleValue($probability);
2485
 
2486
		if ((is_numeric($failures)) && (is_numeric($successes)) && (is_numeric($probability))) {
2487
			if (($failures < 0) || ($successes < 1)) {
2488
				return PHPExcel_Calculation_Functions::NaN();
2489
			}
2490
			if (($probability < 0) || ($probability > 1)) {
2491
				return PHPExcel_Calculation_Functions::NaN();
2492
			}
2493
			if (PHPExcel_Calculation_Functions::getCompatibilityMode() == PHPExcel_Calculation_Functions::COMPATIBILITY_GNUMERIC) {
2494
				if (($failures + $successes - 1) <= 0) {
2495
					return PHPExcel_Calculation_Functions::NaN();
2496
				}
2497
			}
2498
			return (PHPExcel_Calculation_MathTrig::COMBIN($failures + $successes - 1,$successes - 1)) * (pow($probability,$successes)) * (pow(1 - $probability,$failures)) ;
2499
		}
2500
		return PHPExcel_Calculation_Functions::VALUE();
2501
	}	//	function NEGBINOMDIST()
2502
 
2503
 
2504
	/**
2505
	 * NORMDIST
2506
	 *
2507
	 * Returns the normal distribution for the specified mean and standard deviation. This
2508
	 * function has a very wide range of applications in statistics, including hypothesis
2509
	 * testing.
2510
	 *
2511
	 * @param	float		$value
2512
	 * @param	float		$mean		Mean Value
2513
	 * @param	float		$stdDev		Standard Deviation
2514
	 * @param	boolean		$cumulative
2515
	 * @return	float
2516
	 *
2517
	 */
2518
	public static function NORMDIST($value, $mean, $stdDev, $cumulative) {
2519
		$value	= PHPExcel_Calculation_Functions::flattenSingleValue($value);
2520
		$mean	= PHPExcel_Calculation_Functions::flattenSingleValue($mean);
2521
		$stdDev	= PHPExcel_Calculation_Functions::flattenSingleValue($stdDev);
2522
 
2523
		if ((is_numeric($value)) && (is_numeric($mean)) && (is_numeric($stdDev))) {
2524
			if ($stdDev < 0) {
2525
				return PHPExcel_Calculation_Functions::NaN();
2526
			}
2527
			if ((is_numeric($cumulative)) || (is_bool($cumulative))) {
2528
				if ($cumulative) {
2529
					return 0.5 * (1 + PHPExcel_Calculation_Engineering::_erfVal(($value - $mean) / ($stdDev * sqrt(2))));
2530
				} else {
2531
					return (1 / (SQRT2PI * $stdDev)) * exp(0 - (pow($value - $mean,2) / (2 * ($stdDev * $stdDev))));
2532
				}
2533
			}
2534
		}
2535
		return PHPExcel_Calculation_Functions::VALUE();
2536
	}	//	function NORMDIST()
2537
 
2538
 
2539
	/**
2540
	 * NORMINV
2541
	 *
2542
	 * Returns the inverse of the normal cumulative distribution for the specified mean and standard deviation.
2543
	 *
2544
	 * @param	float		$value
2545
	 * @param	float		$mean		Mean Value
2546
	 * @param	float		$stdDev		Standard Deviation
2547
	 * @return	float
2548
	 *
2549
	 */
2550
	public static function NORMINV($probability,$mean,$stdDev) {
2551
		$probability	= PHPExcel_Calculation_Functions::flattenSingleValue($probability);
2552
		$mean			= PHPExcel_Calculation_Functions::flattenSingleValue($mean);
2553
		$stdDev			= PHPExcel_Calculation_Functions::flattenSingleValue($stdDev);
2554
 
2555
		if ((is_numeric($probability)) && (is_numeric($mean)) && (is_numeric($stdDev))) {
2556
			if (($probability < 0) || ($probability > 1)) {
2557
				return PHPExcel_Calculation_Functions::NaN();
2558
			}
2559
			if ($stdDev < 0) {
2560
				return PHPExcel_Calculation_Functions::NaN();
2561
			}
2562
			return (self::_inverse_ncdf($probability) * $stdDev) + $mean;
2563
		}
2564
		return PHPExcel_Calculation_Functions::VALUE();
2565
	}	//	function NORMINV()
2566
 
2567
 
2568
	/**
2569
	 * NORMSDIST
2570
	 *
2571
	 * Returns the standard normal cumulative distribution function. The distribution has
2572
	 * a mean of 0 (zero) and a standard deviation of one. Use this function in place of a
2573
	 * table of standard normal curve areas.
2574
	 *
2575
	 * @param	float		$value
2576
	 * @return	float
2577
	 */
2578
	public static function NORMSDIST($value) {
2579
		$value	= PHPExcel_Calculation_Functions::flattenSingleValue($value);
2580
 
2581
		return self::NORMDIST($value, 0, 1, True);
2582
	}	//	function NORMSDIST()
2583
 
2584
 
2585
	/**
2586
	 * NORMSINV
2587
	 *
2588
	 * Returns the inverse of the standard normal cumulative distribution
2589
	 *
2590
	 * @param	float		$value
2591
	 * @return	float
2592
	 */
2593
	public static function NORMSINV($value) {
2594
		return self::NORMINV($value, 0, 1);
2595
	}	//	function NORMSINV()
2596
 
2597
 
2598
	/**
2599
	 * PERCENTILE
2600
	 *
2601
	 * Returns the nth percentile of values in a range..
2602
	 *
2603
	 * Excel Function:
2604
	 *		PERCENTILE(value1[,value2[, ...]],entry)
2605
	 *
2606
	 * @access	public
2607
	 * @category Statistical Functions
2608
	 * @param	mixed		$arg,...		Data values
2609
	 * @param	float		$entry			Percentile value in the range 0..1, inclusive.
2610
	 * @return	float
2611
	 */
2612
	public static function PERCENTILE() {
2613
		$aArgs = PHPExcel_Calculation_Functions::flattenArray(func_get_args());
2614
 
2615
		// Calculate
2616
		$entry = array_pop($aArgs);
2617
 
2618
		if ((is_numeric($entry)) && (!is_string($entry))) {
2619
			if (($entry < 0) || ($entry > 1)) {
2620
				return PHPExcel_Calculation_Functions::NaN();
2621
			}
2622
			$mArgs = array();
2623
			foreach ($aArgs as $arg) {
2624
				// Is it a numeric value?
2625
				if ((is_numeric($arg)) && (!is_string($arg))) {
2626
					$mArgs[] = $arg;
2627
				}
2628
			}
2629
			$mValueCount = count($mArgs);
2630
			if ($mValueCount > 0) {
2631
				sort($mArgs);
2632
				$count = self::COUNT($mArgs);
2633
				$index = $entry * ($count-1);
2634
				$iBase = floor($index);
2635
				if ($index == $iBase) {
2636
					return $mArgs[$index];
2637
				} else {
2638
					$iNext = $iBase + 1;
2639
					$iProportion = $index - $iBase;
2640
					return $mArgs[$iBase] + (($mArgs[$iNext] - $mArgs[$iBase]) * $iProportion) ;
2641
				}
2642
			}
2643
		}
2644
		return PHPExcel_Calculation_Functions::VALUE();
2645
	}	//	function PERCENTILE()
2646
 
2647
 
2648
	/**
2649
	 * PERCENTRANK
2650
	 *
2651
	 * Returns the rank of a value in a data set as a percentage of the data set.
2652
	 *
2653
	 * @param	array of number		An array of, or a reference to, a list of numbers.
2654
	 * @param	number				The number whose rank you want to find.
2655
	 * @param	number				The number of significant digits for the returned percentage value.
2656
	 * @return	float
2657
	 */
2658
	public static function PERCENTRANK($valueSet,$value,$significance=3) {
2659
		$valueSet	= PHPExcel_Calculation_Functions::flattenArray($valueSet);
2660
		$value		= PHPExcel_Calculation_Functions::flattenSingleValue($value);
2661
		$significance	= (is_null($significance))	? 3 :	(integer) PHPExcel_Calculation_Functions::flattenSingleValue($significance);
2662
 
2663
		foreach($valueSet as $key => $valueEntry) {
2664
			if (!is_numeric($valueEntry)) {
2665
				unset($valueSet[$key]);
2666
			}
2667
		}
2668
		sort($valueSet,SORT_NUMERIC);
2669
		$valueCount = count($valueSet);
2670
		if ($valueCount == 0) {
2671
			return PHPExcel_Calculation_Functions::NaN();
2672
		}
2673
 
2674
		$valueAdjustor = $valueCount - 1;
2675
		if (($value < $valueSet[0]) || ($value > $valueSet[$valueAdjustor])) {
2676
			return PHPExcel_Calculation_Functions::NA();
2677
		}
2678
 
2679
		$pos = array_search($value,$valueSet);
2680
		if ($pos === False) {
2681
			$pos = 0;
2682
			$testValue = $valueSet[0];
2683
			while ($testValue < $value) {
2684
				$testValue = $valueSet[++$pos];
2685
			}
2686
			--$pos;
2687
			$pos += (($value - $valueSet[$pos]) / ($testValue - $valueSet[$pos]));
2688
		}
2689
 
2690
		return round($pos / $valueAdjustor,$significance);
2691
	}	//	function PERCENTRANK()
2692
 
2693
 
2694
	/**
2695
	 * PERMUT
2696
	 *
2697
	 * Returns the number of permutations for a given number of objects that can be
2698
	 *		selected from number objects. A permutation is any set or subset of objects or
2699
	 *		events where internal order is significant. Permutations are different from
2700
	 *		combinations, for which the internal order is not significant. Use this function
2701
	 *		for lottery-style probability calculations.
2702
	 *
2703
	 * @param	int		$numObjs	Number of different objects
2704
	 * @param	int		$numInSet	Number of objects in each permutation
2705
	 * @return	int		Number of permutations
2706
	 */
2707
	public static function PERMUT($numObjs,$numInSet) {
2708
		$numObjs	= PHPExcel_Calculation_Functions::flattenSingleValue($numObjs);
2709
		$numInSet	= PHPExcel_Calculation_Functions::flattenSingleValue($numInSet);
2710
 
2711
		if ((is_numeric($numObjs)) && (is_numeric($numInSet))) {
2712
			$numInSet = floor($numInSet);
2713
			if ($numObjs < $numInSet) {
2714
				return PHPExcel_Calculation_Functions::NaN();
2715
			}
2716
			return round(PHPExcel_Calculation_MathTrig::FACT($numObjs) / PHPExcel_Calculation_MathTrig::FACT($numObjs - $numInSet));
2717
		}
2718
		return PHPExcel_Calculation_Functions::VALUE();
2719
	}	//	function PERMUT()
2720
 
2721
 
2722
	/**
2723
	 * POISSON
2724
	 *
2725
	 * Returns the Poisson distribution. A common application of the Poisson distribution
2726
	 * is predicting the number of events over a specific time, such as the number of
2727
	 * cars arriving at a toll plaza in 1 minute.
2728
	 *
2729
	 * @param	float		$value
2730
	 * @param	float		$mean		Mean Value
2731
	 * @param	boolean		$cumulative
2732
	 * @return	float
2733
	 *
2734
	 */
2735
	public static function POISSON($value, $mean, $cumulative) {
2736
		$value	= PHPExcel_Calculation_Functions::flattenSingleValue($value);
2737
		$mean	= PHPExcel_Calculation_Functions::flattenSingleValue($mean);
2738
 
2739
		if ((is_numeric($value)) && (is_numeric($mean))) {
2740
			if (($value <= 0) || ($mean <= 0)) {
2741
				return PHPExcel_Calculation_Functions::NaN();
2742
			}
2743
			if ((is_numeric($cumulative)) || (is_bool($cumulative))) {
2744
				if ($cumulative) {
2745
					$summer = 0;
2746
					for ($i = 0; $i <= floor($value); ++$i) {
2747
						$summer += pow($mean,$i) / PHPExcel_Calculation_MathTrig::FACT($i);
2748
					}
2749
					return exp(0-$mean) * $summer;
2750
				} else {
2751
					return (exp(0-$mean) * pow($mean,$value)) / PHPExcel_Calculation_MathTrig::FACT($value);
2752
				}
2753
			}
2754
		}
2755
		return PHPExcel_Calculation_Functions::VALUE();
2756
	}	//	function POISSON()
2757
 
2758
 
2759
	/**
2760
	 * QUARTILE
2761
	 *
2762
	 * Returns the quartile of a data set.
2763
	 *
2764
	 * Excel Function:
2765
	 *		QUARTILE(value1[,value2[, ...]],entry)
2766
	 *
2767
	 * @access	public
2768
	 * @category Statistical Functions
2769
	 * @param	mixed		$arg,...		Data values
2770
	 * @param	int			$entry			Quartile value in the range 1..3, inclusive.
2771
	 * @return	float
2772
	 */
2773
	public static function QUARTILE() {
2774
		$aArgs = PHPExcel_Calculation_Functions::flattenArray(func_get_args());
2775
 
2776
		// Calculate
2777
		$entry = floor(array_pop($aArgs));
2778
 
2779
		if ((is_numeric($entry)) && (!is_string($entry))) {
2780
			$entry /= 4;
2781
			if (($entry < 0) || ($entry > 1)) {
2782
				return PHPExcel_Calculation_Functions::NaN();
2783
			}
2784
			return self::PERCENTILE($aArgs,$entry);
2785
		}
2786
		return PHPExcel_Calculation_Functions::VALUE();
2787
	}	//	function QUARTILE()
2788
 
2789
 
2790
	/**
2791
	 * RANK
2792
	 *
2793
	 * Returns the rank of a number in a list of numbers.
2794
	 *
2795
	 * @param	number				The number whose rank you want to find.
2796
	 * @param	array of number		An array of, or a reference to, a list of numbers.
2797
	 * @param	mixed				Order to sort the values in the value set
2798
	 * @return	float
2799
	 */
2800
	public static function RANK($value,$valueSet,$order=0) {
2801
		$value = PHPExcel_Calculation_Functions::flattenSingleValue($value);
2802
		$valueSet = PHPExcel_Calculation_Functions::flattenArray($valueSet);
2803
		$order	= (is_null($order))	? 0 :	(integer) PHPExcel_Calculation_Functions::flattenSingleValue($order);
2804
 
2805
		foreach($valueSet as $key => $valueEntry) {
2806
			if (!is_numeric($valueEntry)) {
2807
				unset($valueSet[$key]);
2808
			}
2809
		}
2810
 
2811
		if ($order == 0) {
2812
			rsort($valueSet,SORT_NUMERIC);
2813
		} else {
2814
			sort($valueSet,SORT_NUMERIC);
2815
		}
2816
		$pos = array_search($value,$valueSet);
2817
		if ($pos === False) {
2818
			return PHPExcel_Calculation_Functions::NA();
2819
		}
2820
 
2821
		return ++$pos;
2822
	}	//	function RANK()
2823
 
2824
 
2825
	/**
2826
	 * RSQ
2827
	 *
2828
	 * Returns the square of the Pearson product moment correlation coefficient through data points in known_y's and known_x's.
2829
	 *
2830
	 * @param	array of mixed		Data Series Y
2831
	 * @param	array of mixed		Data Series X
2832
	 * @return	float
2833
	 */
2834
	public static function RSQ($yValues,$xValues) {
2835
		if (!self::_checkTrendArrays($yValues,$xValues)) {
2836
			return PHPExcel_Calculation_Functions::VALUE();
2837
		}
2838
		$yValueCount = count($yValues);
2839
		$xValueCount = count($xValues);
2840
 
2841
		if (($yValueCount == 0) || ($yValueCount != $xValueCount)) {
2842
			return PHPExcel_Calculation_Functions::NA();
2843
		} elseif ($yValueCount == 1) {
2844
			return PHPExcel_Calculation_Functions::DIV0();
2845
		}
2846
 
2847
		$bestFitLinear = trendClass::calculate(trendClass::TREND_LINEAR,$yValues,$xValues);
2848
		return $bestFitLinear->getGoodnessOfFit();
2849
	}	//	function RSQ()
2850
 
2851
 
2852
	/**
2853
	 * SKEW
2854
	 *
2855
	 * Returns the skewness of a distribution. Skewness characterizes the degree of asymmetry
2856
	 * of a distribution around its mean. Positive skewness indicates a distribution with an
2857
	 * asymmetric tail extending toward more positive values. Negative skewness indicates a
2858
	 * distribution with an asymmetric tail extending toward more negative values.
2859
	 *
2860
	 * @param	array	Data Series
2861
	 * @return	float
2862
	 */
2863
	public static function SKEW() {
2864
		$aArgs = PHPExcel_Calculation_Functions::flattenArrayIndexed(func_get_args());
2865
		$mean = self::AVERAGE($aArgs);
2866
		$stdDev = self::STDEV($aArgs);
2867
 
2868
		$count = $summer = 0;
2869
		// Loop through arguments
2870
		foreach ($aArgs as $k => $arg) {
2871
			if ((is_bool($arg)) &&
2872
				(!PHPExcel_Calculation_Functions::isMatrixValue($k))) {
2873
			} else {
2874
				// Is it a numeric value?
2875
				if ((is_numeric($arg)) && (!is_string($arg))) {
2876
					$summer += pow((($arg - $mean) / $stdDev),3) ;
2877
					++$count;
2878
				}
2879
			}
2880
		}
2881
 
2882
		// Return
2883
		if ($count > 2) {
2884
			return $summer * ($count / (($count-1) * ($count-2)));
2885
		}
2886
		return PHPExcel_Calculation_Functions::DIV0();
2887
	}	//	function SKEW()
2888
 
2889
 
2890
	/**
2891
	 * SLOPE
2892
	 *
2893
	 * Returns the slope of the linear regression line through data points in known_y's and known_x's.
2894
	 *
2895
	 * @param	array of mixed		Data Series Y
2896
	 * @param	array of mixed		Data Series X
2897
	 * @return	float
2898
	 */
2899
	public static function SLOPE($yValues,$xValues) {
2900
		if (!self::_checkTrendArrays($yValues,$xValues)) {
2901
			return PHPExcel_Calculation_Functions::VALUE();
2902
		}
2903
		$yValueCount = count($yValues);
2904
		$xValueCount = count($xValues);
2905
 
2906
		if (($yValueCount == 0) || ($yValueCount != $xValueCount)) {
2907
			return PHPExcel_Calculation_Functions::NA();
2908
		} elseif ($yValueCount == 1) {
2909
			return PHPExcel_Calculation_Functions::DIV0();
2910
		}
2911
 
2912
		$bestFitLinear = trendClass::calculate(trendClass::TREND_LINEAR,$yValues,$xValues);
2913
		return $bestFitLinear->getSlope();
2914
	}	//	function SLOPE()
2915
 
2916
 
2917
	/**
2918
	 * SMALL
2919
	 *
2920
	 * Returns the nth smallest value in a data set. You can use this function to
2921
	 *		select a value based on its relative standing.
2922
	 *
2923
	 * Excel Function:
2924
	 *		SMALL(value1[,value2[, ...]],entry)
2925
	 *
2926
	 * @access	public
2927
	 * @category Statistical Functions
2928
	 * @param	mixed		$arg,...		Data values
2929
	 * @param	int			$entry			Position (ordered from the smallest) in the array or range of data to return
2930
	 * @return	float
2931
	 */
2932
	public static function SMALL() {
2933
		$aArgs = PHPExcel_Calculation_Functions::flattenArray(func_get_args());
2934
 
2935
		// Calculate
2936
		$entry = array_pop($aArgs);
2937
 
2938
		if ((is_numeric($entry)) && (!is_string($entry))) {
2939
			$mArgs = array();
2940
			foreach ($aArgs as $arg) {
2941
				// Is it a numeric value?
2942
				if ((is_numeric($arg)) && (!is_string($arg))) {
2943
					$mArgs[] = $arg;
2944
				}
2945
			}
2946
			$count = self::COUNT($mArgs);
2947
			$entry = floor(--$entry);
2948
			if (($entry < 0) || ($entry >= $count) || ($count == 0)) {
2949
				return PHPExcel_Calculation_Functions::NaN();
2950
			}
2951
			sort($mArgs);
2952
			return $mArgs[$entry];
2953
		}
2954
		return PHPExcel_Calculation_Functions::VALUE();
2955
	}	//	function SMALL()
2956
 
2957
 
2958
	/**
2959
	 * STANDARDIZE
2960
	 *
2961
	 * Returns a normalized value from a distribution characterized by mean and standard_dev.
2962
	 *
2963
	 * @param	float	$value		Value to normalize
2964
	 * @param	float	$mean		Mean Value
2965
	 * @param	float	$stdDev		Standard Deviation
2966
	 * @return	float	Standardized value
2967
	 */
2968
	public static function STANDARDIZE($value,$mean,$stdDev) {
2969
		$value	= PHPExcel_Calculation_Functions::flattenSingleValue($value);
2970
		$mean	= PHPExcel_Calculation_Functions::flattenSingleValue($mean);
2971
		$stdDev	= PHPExcel_Calculation_Functions::flattenSingleValue($stdDev);
2972
 
2973
		if ((is_numeric($value)) && (is_numeric($mean)) && (is_numeric($stdDev))) {
2974
			if ($stdDev <= 0) {
2975
				return PHPExcel_Calculation_Functions::NaN();
2976
			}
2977
			return ($value - $mean) / $stdDev ;
2978
		}
2979
		return PHPExcel_Calculation_Functions::VALUE();
2980
	}	//	function STANDARDIZE()
2981
 
2982
 
2983
	/**
2984
	 * STDEV
2985
	 *
2986
	 * Estimates standard deviation based on a sample. The standard deviation is a measure of how
2987
	 *		widely values are dispersed from the average value (the mean).
2988
	 *
2989
	 * Excel Function:
2990
	 *		STDEV(value1[,value2[, ...]])
2991
	 *
2992
	 * @access	public
2993
	 * @category Statistical Functions
2994
	 * @param	mixed		$arg,...		Data values
2995
	 * @return	float
2996
	 */
2997
	public static function STDEV() {
2998
		$aArgs = PHPExcel_Calculation_Functions::flattenArrayIndexed(func_get_args());
2999
 
3000
		// Return value
3001
		$returnValue = null;
3002
 
3003
		$aMean = self::AVERAGE($aArgs);
3004
		if (!is_null($aMean)) {
3005
			$aCount = -1;
3006
			foreach ($aArgs as $k => $arg) {
3007
				if ((is_bool($arg)) &&
3008
					((!PHPExcel_Calculation_Functions::isCellValue($k)) || (PHPExcel_Calculation_Functions::getCompatibilityMode() == PHPExcel_Calculation_Functions::COMPATIBILITY_OPENOFFICE))) {
3009
					$arg = (integer) $arg;
3010
				}
3011
				// Is it a numeric value?
3012
				if ((is_numeric($arg)) && (!is_string($arg))) {
3013
					if (is_null($returnValue)) {
3014
						$returnValue = pow(($arg - $aMean),2);
3015
					} else {
3016
						$returnValue += pow(($arg - $aMean),2);
3017
					}
3018
					++$aCount;
3019
				}
3020
			}
3021
 
3022
			// Return
3023
			if (($aCount > 0) && ($returnValue >= 0)) {
3024
				return sqrt($returnValue / $aCount);
3025
			}
3026
		}
3027
		return PHPExcel_Calculation_Functions::DIV0();
3028
	}	//	function STDEV()
3029
 
3030
 
3031
	/**
3032
	 * STDEVA
3033
	 *
3034
	 * Estimates standard deviation based on a sample, including numbers, text, and logical values
3035
	 *
3036
	 * Excel Function:
3037
	 *		STDEVA(value1[,value2[, ...]])
3038
	 *
3039
	 * @access	public
3040
	 * @category Statistical Functions
3041
	 * @param	mixed		$arg,...		Data values
3042
	 * @return	float
3043
	 */
3044
	public static function STDEVA() {
3045
		$aArgs = PHPExcel_Calculation_Functions::flattenArrayIndexed(func_get_args());
3046
 
3047
		// Return value
3048
		$returnValue = null;
3049
 
3050
		$aMean = self::AVERAGEA($aArgs);
3051
		if (!is_null($aMean)) {
3052
			$aCount = -1;
3053
			foreach ($aArgs as $k => $arg) {
3054
				if ((is_bool($arg)) &&
3055
					(!PHPExcel_Calculation_Functions::isMatrixValue($k))) {
3056
				} else {
3057
					// Is it a numeric value?
3058
					if ((is_numeric($arg)) || (is_bool($arg)) || ((is_string($arg) & ($arg != '')))) {
3059
						if (is_bool($arg)) {
3060
							$arg = (integer) $arg;
3061
						} elseif (is_string($arg)) {
3062
							$arg = 0;
3063
						}
3064
						if (is_null($returnValue)) {
3065
							$returnValue = pow(($arg - $aMean),2);
3066
						} else {
3067
							$returnValue += pow(($arg - $aMean),2);
3068
						}
3069
						++$aCount;
3070
					}
3071
				}
3072
			}
3073
 
3074
			// Return
3075
			if (($aCount > 0) && ($returnValue >= 0)) {
3076
				return sqrt($returnValue / $aCount);
3077
			}
3078
		}
3079
		return PHPExcel_Calculation_Functions::DIV0();
3080
	}	//	function STDEVA()
3081
 
3082
 
3083
	/**
3084
	 * STDEVP
3085
	 *
3086
	 * Calculates standard deviation based on the entire population
3087
	 *
3088
	 * Excel Function:
3089
	 *		STDEVP(value1[,value2[, ...]])
3090
	 *
3091
	 * @access	public
3092
	 * @category Statistical Functions
3093
	 * @param	mixed		$arg,...		Data values
3094
	 * @return	float
3095
	 */
3096
	public static function STDEVP() {
3097
		$aArgs = PHPExcel_Calculation_Functions::flattenArrayIndexed(func_get_args());
3098
 
3099
		// Return value
3100
		$returnValue = null;
3101
 
3102
		$aMean = self::AVERAGE($aArgs);
3103
		if (!is_null($aMean)) {
3104
			$aCount = 0;
3105
			foreach ($aArgs as $k => $arg) {
3106
				if ((is_bool($arg)) &&
3107
					((!PHPExcel_Calculation_Functions::isCellValue($k)) || (PHPExcel_Calculation_Functions::getCompatibilityMode() == PHPExcel_Calculation_Functions::COMPATIBILITY_OPENOFFICE))) {
3108
					$arg = (integer) $arg;
3109
				}
3110
				// Is it a numeric value?
3111
				if ((is_numeric($arg)) && (!is_string($arg))) {
3112
					if (is_null($returnValue)) {
3113
						$returnValue = pow(($arg - $aMean),2);
3114
					} else {
3115
						$returnValue += pow(($arg - $aMean),2);
3116
					}
3117
					++$aCount;
3118
				}
3119
			}
3120
 
3121
			// Return
3122
			if (($aCount > 0) && ($returnValue >= 0)) {
3123
				return sqrt($returnValue / $aCount);
3124
			}
3125
		}
3126
		return PHPExcel_Calculation_Functions::DIV0();
3127
	}	//	function STDEVP()
3128
 
3129
 
3130
	/**
3131
	 * STDEVPA
3132
	 *
3133
	 * Calculates standard deviation based on the entire population, including numbers, text, and logical values
3134
	 *
3135
	 * Excel Function:
3136
	 *		STDEVPA(value1[,value2[, ...]])
3137
	 *
3138
	 * @access	public
3139
	 * @category Statistical Functions
3140
	 * @param	mixed		$arg,...		Data values
3141
	 * @return	float
3142
	 */
3143
	public static function STDEVPA() {
3144
		$aArgs = PHPExcel_Calculation_Functions::flattenArrayIndexed(func_get_args());
3145
 
3146
		// Return value
3147
		$returnValue = null;
3148
 
3149
		$aMean = self::AVERAGEA($aArgs);
3150
		if (!is_null($aMean)) {
3151
			$aCount = 0;
3152
			foreach ($aArgs as $k => $arg) {
3153
				if ((is_bool($arg)) &&
3154
					(!PHPExcel_Calculation_Functions::isMatrixValue($k))) {
3155
				} else {
3156
					// Is it a numeric value?
3157
					if ((is_numeric($arg)) || (is_bool($arg)) || ((is_string($arg) & ($arg != '')))) {
3158
						if (is_bool($arg)) {
3159
							$arg = (integer) $arg;
3160
						} elseif (is_string($arg)) {
3161
							$arg = 0;
3162
						}
3163
						if (is_null($returnValue)) {
3164
							$returnValue = pow(($arg - $aMean),2);
3165
						} else {
3166
							$returnValue += pow(($arg - $aMean),2);
3167
						}
3168
						++$aCount;
3169
					}
3170
				}
3171
			}
3172
 
3173
			// Return
3174
			if (($aCount > 0) && ($returnValue >= 0)) {
3175
				return sqrt($returnValue / $aCount);
3176
			}
3177
		}
3178
		return PHPExcel_Calculation_Functions::DIV0();
3179
	}	//	function STDEVPA()
3180
 
3181
 
3182
	/**
3183
	 * STEYX
3184
	 *
3185
	 * Returns the standard error of the predicted y-value for each x in the regression.
3186
	 *
3187
	 * @param	array of mixed		Data Series Y
3188
	 * @param	array of mixed		Data Series X
3189
	 * @return	float
3190
	 */
3191
	public static function STEYX($yValues,$xValues) {
3192
		if (!self::_checkTrendArrays($yValues,$xValues)) {
3193
			return PHPExcel_Calculation_Functions::VALUE();
3194
		}
3195
		$yValueCount = count($yValues);
3196
		$xValueCount = count($xValues);
3197
 
3198
		if (($yValueCount == 0) || ($yValueCount != $xValueCount)) {
3199
			return PHPExcel_Calculation_Functions::NA();
3200
		} elseif ($yValueCount == 1) {
3201
			return PHPExcel_Calculation_Functions::DIV0();
3202
		}
3203
 
3204
		$bestFitLinear = trendClass::calculate(trendClass::TREND_LINEAR,$yValues,$xValues);
3205
		return $bestFitLinear->getStdevOfResiduals();
3206
	}	//	function STEYX()
3207
 
3208
 
3209
	/**
3210
	 * TDIST
3211
	 *
3212
	 * Returns the probability of Student's T distribution.
3213
	 *
3214
	 * @param	float		$value			Value for the function
3215
	 * @param	float		$degrees		degrees of freedom
3216
	 * @param	float		$tails			number of tails (1 or 2)
3217
	 * @return	float
3218
	 */
3219
	public static function TDIST($value, $degrees, $tails) {
3220
		$value		= PHPExcel_Calculation_Functions::flattenSingleValue($value);
3221
		$degrees	= floor(PHPExcel_Calculation_Functions::flattenSingleValue($degrees));
3222
		$tails		= floor(PHPExcel_Calculation_Functions::flattenSingleValue($tails));
3223
 
3224
		if ((is_numeric($value)) && (is_numeric($degrees)) && (is_numeric($tails))) {
3225
			if (($value < 0) || ($degrees < 1) || ($tails < 1) || ($tails > 2)) {
3226
				return PHPExcel_Calculation_Functions::NaN();
3227
			}
3228
			//	tdist, which finds the probability that corresponds to a given value
3229
			//	of t with k degrees of freedom. This algorithm is translated from a
3230
			//	pascal function on p81 of "Statistical Computing in Pascal" by D
3231
			//	Cooke, A H Craven & G M Clark (1985: Edward Arnold (Pubs.) Ltd:
3232
			//	London). The above Pascal algorithm is itself a translation of the
3233
			//	fortran algoritm "AS 3" by B E Cooper of the Atlas Computer
3234
			//	Laboratory as reported in (among other places) "Applied Statistics
3235
			//	Algorithms", editied by P Griffiths and I D Hill (1985; Ellis
3236
			//	Horwood Ltd.; W. Sussex, England).
3237
			$tterm = $degrees;
3238
			$ttheta = atan2($value,sqrt($tterm));
3239
			$tc = cos($ttheta);
3240
			$ts = sin($ttheta);
3241
			$tsum = 0;
3242
 
3243
			if (($degrees % 2) == 1) {
3244
				$ti = 3;
3245
				$tterm = $tc;
3246
			} else {
3247
				$ti = 2;
3248
				$tterm = 1;
3249
			}
3250
 
3251
			$tsum = $tterm;
3252
			while ($ti < $degrees) {
3253
				$tterm *= $tc * $tc * ($ti - 1) / $ti;
3254
				$tsum += $tterm;
3255
				$ti += 2;
3256
			}
3257
			$tsum *= $ts;
3258
			if (($degrees % 2) == 1) { $tsum = M_2DIVPI * ($tsum + $ttheta); }
3259
			$tValue = 0.5 * (1 + $tsum);
3260
			if ($tails == 1) {
3261
				return 1 - abs($tValue);
3262
			} else {
3263
				return 1 - abs((1 - $tValue) - $tValue);
3264
			}
3265
		}
3266
		return PHPExcel_Calculation_Functions::VALUE();
3267
	}	//	function TDIST()
3268
 
3269
 
3270
	/**
3271
	 * TINV
3272
	 *
3273
	 * Returns the one-tailed probability of the chi-squared distribution.
3274
	 *
3275
	 * @param	float		$probability	Probability for the function
3276
	 * @param	float		$degrees		degrees of freedom
3277
	 * @return	float
3278
	 */
3279
	public static function TINV($probability, $degrees) {
3280
		$probability	= PHPExcel_Calculation_Functions::flattenSingleValue($probability);
3281
		$degrees		= floor(PHPExcel_Calculation_Functions::flattenSingleValue($degrees));
3282
 
3283
		if ((is_numeric($probability)) && (is_numeric($degrees))) {
3284
			$xLo = 100;
3285
			$xHi = 0;
3286
 
3287
			$x = $xNew = 1;
3288
			$dx	= 1;
3289
			$i = 0;
3290
 
3291
			while ((abs($dx) > PRECISION) && ($i++ < MAX_ITERATIONS)) {
3292
				// Apply Newton-Raphson step
3293
				$result = self::TDIST($x, $degrees, 2);
3294
				$error = $result - $probability;
3295
				if ($error == 0.0) {
3296
					$dx = 0;
3297
				} elseif ($error < 0.0) {
3298
					$xLo = $x;
3299
				} else {
3300
					$xHi = $x;
3301
				}
3302
				// Avoid division by zero
3303
				if ($result != 0.0) {
3304
					$dx = $error / $result;
3305
					$xNew = $x - $dx;
3306
				}
3307
				// If the NR fails to converge (which for example may be the
3308
				// case if the initial guess is too rough) we apply a bisection
3309
				// step to determine a more narrow interval around the root.
3310
				if (($xNew < $xLo) || ($xNew > $xHi) || ($result == 0.0)) {
3311
					$xNew = ($xLo + $xHi) / 2;
3312
					$dx = $xNew - $x;
3313
				}
3314
				$x = $xNew;
3315
			}
3316
			if ($i == MAX_ITERATIONS) {
3317
				return PHPExcel_Calculation_Functions::NA();
3318
			}
3319
			return round($x,12);
3320
		}
3321
		return PHPExcel_Calculation_Functions::VALUE();
3322
	}	//	function TINV()
3323
 
3324
 
3325
	/**
3326
	 * TREND
3327
	 *
3328
	 * Returns values along a linear trend
3329
	 *
3330
	 * @param	array of mixed		Data Series Y
3331
	 * @param	array of mixed		Data Series X
3332
	 * @param	array of mixed		Values of X for which we want to find Y
3333
	 * @param	boolean				A logical value specifying whether to force the intersect to equal 0.
3334
	 * @return	array of float
3335
	 */
3336
	public static function TREND($yValues,$xValues=array(),$newValues=array(),$const=True) {
3337
		$yValues = PHPExcel_Calculation_Functions::flattenArray($yValues);
3338
		$xValues = PHPExcel_Calculation_Functions::flattenArray($xValues);
3339
		$newValues = PHPExcel_Calculation_Functions::flattenArray($newValues);
3340
		$const	= (is_null($const))	? True :	(boolean) PHPExcel_Calculation_Functions::flattenSingleValue($const);
3341
 
3342
		$bestFitLinear = trendClass::calculate(trendClass::TREND_LINEAR,$yValues,$xValues,$const);
3343
		if (empty($newValues)) {
3344
			$newValues = $bestFitLinear->getXValues();
3345
		}
3346
 
3347
		$returnArray = array();
3348
		foreach($newValues as $xValue) {
3349
			$returnArray[0][] = $bestFitLinear->getValueOfYForX($xValue);
3350
		}
3351
 
3352
		return $returnArray;
3353
	}	//	function TREND()
3354
 
3355
 
3356
	/**
3357
	 * TRIMMEAN
3358
	 *
3359
	 * Returns the mean of the interior of a data set. TRIMMEAN calculates the mean
3360
	 *		taken by excluding a percentage of data points from the top and bottom tails
3361
	 *		of a data set.
3362
	 *
3363
	 * Excel Function:
3364
	 *		TRIMEAN(value1[,value2[, ...]],$discard)
3365
	 *
3366
	 * @access	public
3367
	 * @category Statistical Functions
3368
	 * @param	mixed		$arg,...		Data values
3369
	 * @param	float		$discard		Percentage to discard
3370
	 * @return	float
3371
	 */
3372
	public static function TRIMMEAN() {
3373
		$aArgs = PHPExcel_Calculation_Functions::flattenArray(func_get_args());
3374
 
3375
		// Calculate
3376
		$percent = array_pop($aArgs);
3377
 
3378
		if ((is_numeric($percent)) && (!is_string($percent))) {
3379
			if (($percent < 0) || ($percent > 1)) {
3380
				return PHPExcel_Calculation_Functions::NaN();
3381
			}
3382
			$mArgs = array();
3383
			foreach ($aArgs as $arg) {
3384
				// Is it a numeric value?
3385
				if ((is_numeric($arg)) && (!is_string($arg))) {
3386
					$mArgs[] = $arg;
3387
				}
3388
			}
3389
			$discard = floor(self::COUNT($mArgs) * $percent / 2);
3390
			sort($mArgs);
3391
			for ($i=0; $i < $discard; ++$i) {
3392
				array_pop($mArgs);
3393
				array_shift($mArgs);
3394
			}
3395
			return self::AVERAGE($mArgs);
3396
		}
3397
		return PHPExcel_Calculation_Functions::VALUE();
3398
	}	//	function TRIMMEAN()
3399
 
3400
 
3401
	/**
3402
	 * VARFunc
3403
	 *
3404
	 * Estimates variance based on a sample.
3405
	 *
3406
	 * Excel Function:
3407
	 *		VAR(value1[,value2[, ...]])
3408
	 *
3409
	 * @access	public
3410
	 * @category Statistical Functions
3411
	 * @param	mixed		$arg,...		Data values
3412
	 * @return	float
3413
	 */
3414
	public static function VARFunc() {
3415
		// Return value
3416
		$returnValue = PHPExcel_Calculation_Functions::DIV0();
3417
 
3418
		$summerA = $summerB = 0;
3419
 
3420
		// Loop through arguments
3421
		$aArgs = PHPExcel_Calculation_Functions::flattenArray(func_get_args());
3422
		$aCount = 0;
3423
		foreach ($aArgs as $arg) {
3424
			if (is_bool($arg)) { $arg = (integer) $arg; }
3425
			// Is it a numeric value?
3426
			if ((is_numeric($arg)) && (!is_string($arg))) {
3427
				$summerA += ($arg * $arg);
3428
				$summerB += $arg;
3429
				++$aCount;
3430
			}
3431
		}
3432
 
3433
		// Return
3434
		if ($aCount > 1) {
3435
			$summerA *= $aCount;
3436
			$summerB *= $summerB;
3437
			$returnValue = ($summerA - $summerB) / ($aCount * ($aCount - 1));
3438
		}
3439
		return $returnValue;
3440
	}	//	function VARFunc()
3441
 
3442
 
3443
	/**
3444
	 * VARA
3445
	 *
3446
	 * Estimates variance based on a sample, including numbers, text, and logical values
3447
	 *
3448
	 * Excel Function:
3449
	 *		VARA(value1[,value2[, ...]])
3450
	 *
3451
	 * @access	public
3452
	 * @category Statistical Functions
3453
	 * @param	mixed		$arg,...		Data values
3454
	 * @return	float
3455
	 */
3456
	public static function VARA() {
3457
		// Return value
3458
		$returnValue = PHPExcel_Calculation_Functions::DIV0();
3459
 
3460
		$summerA = $summerB = 0;
3461
 
3462
		// Loop through arguments
3463
		$aArgs = PHPExcel_Calculation_Functions::flattenArrayIndexed(func_get_args());
3464
		$aCount = 0;
3465
		foreach ($aArgs as $k => $arg) {
3466
			if ((is_string($arg)) &&
3467
				(PHPExcel_Calculation_Functions::isValue($k))) {
3468
				return PHPExcel_Calculation_Functions::VALUE();
3469
			} elseif ((is_string($arg)) &&
3470
				(!PHPExcel_Calculation_Functions::isMatrixValue($k))) {
3471
			} else {
3472
				// Is it a numeric value?
3473
				if ((is_numeric($arg)) || (is_bool($arg)) || ((is_string($arg) & ($arg != '')))) {
3474
					if (is_bool($arg)) {
3475
						$arg = (integer) $arg;
3476
					} elseif (is_string($arg)) {
3477
						$arg = 0;
3478
					}
3479
					$summerA += ($arg * $arg);
3480
					$summerB += $arg;
3481
					++$aCount;
3482
				}
3483
			}
3484
		}
3485
 
3486
		// Return
3487
		if ($aCount > 1) {
3488
			$summerA *= $aCount;
3489
			$summerB *= $summerB;
3490
			$returnValue = ($summerA - $summerB) / ($aCount * ($aCount - 1));
3491
		}
3492
		return $returnValue;
3493
	}	//	function VARA()
3494
 
3495
 
3496
	/**
3497
	 * VARP
3498
	 *
3499
	 * Calculates variance based on the entire population
3500
	 *
3501
	 * Excel Function:
3502
	 *		VARP(value1[,value2[, ...]])
3503
	 *
3504
	 * @access	public
3505
	 * @category Statistical Functions
3506
	 * @param	mixed		$arg,...		Data values
3507
	 * @return	float
3508
	 */
3509
	public static function VARP() {
3510
		// Return value
3511
		$returnValue = PHPExcel_Calculation_Functions::DIV0();
3512
 
3513
		$summerA = $summerB = 0;
3514
 
3515
		// Loop through arguments
3516
		$aArgs = PHPExcel_Calculation_Functions::flattenArray(func_get_args());
3517
		$aCount = 0;
3518
		foreach ($aArgs as $arg) {
3519
			if (is_bool($arg)) { $arg = (integer) $arg; }
3520
			// Is it a numeric value?
3521
			if ((is_numeric($arg)) && (!is_string($arg))) {
3522
				$summerA += ($arg * $arg);
3523
				$summerB += $arg;
3524
				++$aCount;
3525
			}
3526
		}
3527
 
3528
		// Return
3529
		if ($aCount > 0) {
3530
			$summerA *= $aCount;
3531
			$summerB *= $summerB;
3532
			$returnValue = ($summerA - $summerB) / ($aCount * $aCount);
3533
		}
3534
		return $returnValue;
3535
	}	//	function VARP()
3536
 
3537
 
3538
	/**
3539
	 * VARPA
3540
	 *
3541
	 * Calculates variance based on the entire population, including numbers, text, and logical values
3542
	 *
3543
	 * Excel Function:
3544
	 *		VARPA(value1[,value2[, ...]])
3545
	 *
3546
	 * @access	public
3547
	 * @category Statistical Functions
3548
	 * @param	mixed		$arg,...		Data values
3549
	 * @return	float
3550
	 */
3551
	public static function VARPA() {
3552
		// Return value
3553
		$returnValue = PHPExcel_Calculation_Functions::DIV0();
3554
 
3555
		$summerA = $summerB = 0;
3556
 
3557
		// Loop through arguments
3558
		$aArgs = PHPExcel_Calculation_Functions::flattenArrayIndexed(func_get_args());
3559
		$aCount = 0;
3560
		foreach ($aArgs as $k => $arg) {
3561
			if ((is_string($arg)) &&
3562
				(PHPExcel_Calculation_Functions::isValue($k))) {
3563
				return PHPExcel_Calculation_Functions::VALUE();
3564
			} elseif ((is_string($arg)) &&
3565
				(!PHPExcel_Calculation_Functions::isMatrixValue($k))) {
3566
			} else {
3567
				// Is it a numeric value?
3568
				if ((is_numeric($arg)) || (is_bool($arg)) || ((is_string($arg) & ($arg != '')))) {
3569
					if (is_bool($arg)) {
3570
						$arg = (integer) $arg;
3571
					} elseif (is_string($arg)) {
3572
						$arg = 0;
3573
					}
3574
					$summerA += ($arg * $arg);
3575
					$summerB += $arg;
3576
					++$aCount;
3577
				}
3578
			}
3579
		}
3580
 
3581
		// Return
3582
		if ($aCount > 0) {
3583
			$summerA *= $aCount;
3584
			$summerB *= $summerB;
3585
			$returnValue = ($summerA - $summerB) / ($aCount * $aCount);
3586
		}
3587
		return $returnValue;
3588
	}	//	function VARPA()
3589
 
3590
 
3591
	/**
3592
	 * WEIBULL
3593
	 *
3594
	 * Returns the Weibull distribution. Use this distribution in reliability
3595
	 * analysis, such as calculating a device's mean time to failure.
3596
	 *
3597
	 * @param	float		$value
3598
	 * @param	float		$alpha		Alpha Parameter
3599
	 * @param	float		$beta		Beta Parameter
3600
	 * @param	boolean		$cumulative
3601
	 * @return	float
3602
	 *
3603
	 */
3604
	public static function WEIBULL($value, $alpha, $beta, $cumulative) {
3605
		$value	= PHPExcel_Calculation_Functions::flattenSingleValue($value);
3606
		$alpha	= PHPExcel_Calculation_Functions::flattenSingleValue($alpha);
3607
		$beta	= PHPExcel_Calculation_Functions::flattenSingleValue($beta);
3608
 
3609
		if ((is_numeric($value)) && (is_numeric($alpha)) && (is_numeric($beta))) {
3610
			if (($value < 0) || ($alpha <= 0) || ($beta <= 0)) {
3611
				return PHPExcel_Calculation_Functions::NaN();
3612
			}
3613
			if ((is_numeric($cumulative)) || (is_bool($cumulative))) {
3614
				if ($cumulative) {
3615
					return 1 - exp(0 - pow($value / $beta,$alpha));
3616
				} else {
3617
					return ($alpha / pow($beta,$alpha)) * pow($value,$alpha - 1) * exp(0 - pow($value / $beta,$alpha));
3618
				}
3619
			}
3620
		}
3621
		return PHPExcel_Calculation_Functions::VALUE();
3622
	}	//	function WEIBULL()
3623
 
3624
 
3625
	/**
3626
	 * ZTEST
3627
	 *
3628
	 * Returns the Weibull distribution. Use this distribution in reliability
3629
	 * analysis, such as calculating a device's mean time to failure.
3630
	 *
3631
	 * @param	float		$dataSet
3632
	 * @param	float		$m0		Alpha Parameter
3633
	 * @param	float		$sigma	Beta Parameter
3634
	 * @param	boolean		$cumulative
3635
	 * @return	float
3636
	 *
3637
	 */
3638
	public static function ZTEST($dataSet, $m0, $sigma = NULL) {
3639
		$dataSet	= PHPExcel_Calculation_Functions::flattenArrayIndexed($dataSet);
3640
		$m0			= PHPExcel_Calculation_Functions::flattenSingleValue($m0);
3641
		$sigma		= PHPExcel_Calculation_Functions::flattenSingleValue($sigma);
3642
 
3643
		if (is_null($sigma)) {
3644
			$sigma = self::STDEV($dataSet);
3645
		}
3646
		$n = count($dataSet);
3647
 
3648
		return 1 - self::NORMSDIST((self::AVERAGE($dataSet) - $m0)/($sigma/SQRT($n)));
3649
	}	//	function ZTEST()
3650
 
3651
}	//	class PHPExcel_Calculation_Statistical