Subversion Repositories eFlore/Applications.cel

Rev

Details | Last modification | View Log | RSS feed

Rev Author Line No. Line
2390 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_Shared_Trend
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
require_once PHPEXCEL_ROOT . 'PHPExcel/Shared/trend/linearBestFitClass.php';
30
require_once PHPEXCEL_ROOT . 'PHPExcel/Shared/trend/logarithmicBestFitClass.php';
31
require_once PHPEXCEL_ROOT . 'PHPExcel/Shared/trend/exponentialBestFitClass.php';
32
require_once PHPEXCEL_ROOT . 'PHPExcel/Shared/trend/powerBestFitClass.php';
33
require_once PHPEXCEL_ROOT . 'PHPExcel/Shared/trend/polynomialBestFitClass.php';
34
 
35
 
36
/**
37
 * PHPExcel_trendClass
38
 *
39
 * @category   PHPExcel
40
 * @package    PHPExcel_Shared_Trend
41
 * @copyright  Copyright (c) 2006 - 2013 PHPExcel (http://www.codeplex.com/PHPExcel)
42
 */
43
class trendClass
44
{
45
	const TREND_LINEAR				= 'Linear';
46
	const TREND_LOGARITHMIC			= 'Logarithmic';
47
	const TREND_EXPONENTIAL			= 'Exponential';
48
	const TREND_POWER				= 'Power';
49
	const TREND_POLYNOMIAL_2		= 'Polynomial_2';
50
	const TREND_POLYNOMIAL_3		= 'Polynomial_3';
51
	const TREND_POLYNOMIAL_4		= 'Polynomial_4';
52
	const TREND_POLYNOMIAL_5		= 'Polynomial_5';
53
	const TREND_POLYNOMIAL_6		= 'Polynomial_6';
54
	const TREND_BEST_FIT			= 'Bestfit';
55
	const TREND_BEST_FIT_NO_POLY	= 'Bestfit_no_Polynomials';
56
 
57
	/**
58
	 * Names of the best-fit trend analysis methods
59
	 *
60
	 * @var string[]
61
	 **/
62
	private static $_trendTypes = array( self::TREND_LINEAR,
63
										 self::TREND_LOGARITHMIC,
64
										 self::TREND_EXPONENTIAL,
65
										 self::TREND_POWER
66
									   );
67
	/**
68
	 * Names of the best-fit trend polynomial orders
69
	 *
70
	 * @var string[]
71
	 **/
72
	private static $_trendTypePolyOrders = array( self::TREND_POLYNOMIAL_2,
73
												  self::TREND_POLYNOMIAL_3,
74
												  self::TREND_POLYNOMIAL_4,
75
												  self::TREND_POLYNOMIAL_5,
76
												  self::TREND_POLYNOMIAL_6
77
											    );
78
 
79
	/**
80
	 * Cached results for each method when trying to identify which provides the best fit
81
	 *
82
	 * @var PHPExcel_Best_Fit[]
83
	 **/
84
	private static $_trendCache = array();
85
 
86
 
87
	public static function calculate($trendType=self::TREND_BEST_FIT, $yValues, $xValues=array(), $const=True) {
88
		//	Calculate number of points in each dataset
89
		$nY = count($yValues);
90
		$nX = count($xValues);
91
 
92
		//	Define X Values if necessary
93
		if ($nX == 0) {
94
			$xValues = range(1,$nY);
95
			$nX = $nY;
96
		} elseif ($nY != $nX) {
97
			//	Ensure both arrays of points are the same size
98
			trigger_error("trend(): Number of elements in coordinate arrays do not match.", E_USER_ERROR);
99
		}
100
 
101
		$key = md5($trendType.$const.serialize($yValues).serialize($xValues));
102
		//	Determine which trend method has been requested
103
		switch ($trendType) {
104
			//	Instantiate and return the class for the requested trend method
105
			case self::TREND_LINEAR :
106
			case self::TREND_LOGARITHMIC :
107
			case self::TREND_EXPONENTIAL :
108
			case self::TREND_POWER :
109
				if (!isset(self::$_trendCache[$key])) {
110
					$className = 'PHPExcel_'.$trendType.'_Best_Fit';
111
					self::$_trendCache[$key] = new $className($yValues,$xValues,$const);
112
				}
113
				return self::$_trendCache[$key];
114
				break;
115
			case self::TREND_POLYNOMIAL_2	:
116
			case self::TREND_POLYNOMIAL_3	:
117
			case self::TREND_POLYNOMIAL_4	:
118
			case self::TREND_POLYNOMIAL_5	:
119
			case self::TREND_POLYNOMIAL_6	:
120
				if (!isset(self::$_trendCache[$key])) {
121
					$order = substr($trendType,-1);
122
					self::$_trendCache[$key] = new PHPExcel_Polynomial_Best_Fit($order,$yValues,$xValues,$const);
123
				}
124
				return self::$_trendCache[$key];
125
				break;
126
			case self::TREND_BEST_FIT			:
127
			case self::TREND_BEST_FIT_NO_POLY	:
128
				//	If the request is to determine the best fit regression, then we test each trend line in turn
129
				//	Start by generating an instance of each available trend method
130
				foreach(self::$_trendTypes as $trendMethod) {
131
					$className = 'PHPExcel_'.$trendMethod.'BestFit';
132
					$bestFit[$trendMethod] = new $className($yValues,$xValues,$const);
133
					$bestFitValue[$trendMethod] = $bestFit[$trendMethod]->getGoodnessOfFit();
134
				}
135
				if ($trendType != self::TREND_BEST_FIT_NO_POLY) {
136
					foreach(self::$_trendTypePolyOrders as $trendMethod) {
137
						$order = substr($trendMethod,-1);
138
						$bestFit[$trendMethod] = new PHPExcel_Polynomial_Best_Fit($order,$yValues,$xValues,$const);
139
						if ($bestFit[$trendMethod]->getError()) {
140
							unset($bestFit[$trendMethod]);
141
						} else {
142
							$bestFitValue[$trendMethod] = $bestFit[$trendMethod]->getGoodnessOfFit();
143
						}
144
					}
145
				}
146
				//	Determine which of our trend lines is the best fit, and then we return the instance of that trend class
147
				arsort($bestFitValue);
148
				$bestFitType = key($bestFitValue);
149
				return $bestFit[$bestFitType];
150
				break;
151
			default	:
152
				return false;
153
		}
154
	}	//	function calculate()
155
 
156
}	//	class trendClass