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0,0 → 1,156 |
<?php |
/** |
* PHPExcel |
* |
* Copyright (c) 2006 - 2013 PHPExcel |
* |
* This library is free software; you can redistribute it and/or |
* modify it under the terms of the GNU Lesser General Public |
* License as published by the Free Software Foundation; either |
* version 2.1 of the License, or (at your option) any later version. |
* |
* This library is distributed in the hope that it will be useful, |
* but WITHOUT ANY WARRANTY; without even the implied warranty of |
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
* Lesser General Public License for more details. |
* |
* You should have received a copy of the GNU Lesser General Public |
* License along with this library; if not, write to the Free Software |
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
* |
* @category PHPExcel |
* @package PHPExcel_Shared_Trend |
* @copyright Copyright (c) 2006 - 2013 PHPExcel (http://www.codeplex.com/PHPExcel) |
* @license http://www.gnu.org/licenses/old-licenses/lgpl-2.1.txt LGPL |
* @version ##VERSION##, ##DATE## |
*/ |
|
|
require_once PHPEXCEL_ROOT . 'PHPExcel/Shared/trend/linearBestFitClass.php'; |
require_once PHPEXCEL_ROOT . 'PHPExcel/Shared/trend/logarithmicBestFitClass.php'; |
require_once PHPEXCEL_ROOT . 'PHPExcel/Shared/trend/exponentialBestFitClass.php'; |
require_once PHPEXCEL_ROOT . 'PHPExcel/Shared/trend/powerBestFitClass.php'; |
require_once PHPEXCEL_ROOT . 'PHPExcel/Shared/trend/polynomialBestFitClass.php'; |
|
|
/** |
* PHPExcel_trendClass |
* |
* @category PHPExcel |
* @package PHPExcel_Shared_Trend |
* @copyright Copyright (c) 2006 - 2013 PHPExcel (http://www.codeplex.com/PHPExcel) |
*/ |
class trendClass |
{ |
const TREND_LINEAR = 'Linear'; |
const TREND_LOGARITHMIC = 'Logarithmic'; |
const TREND_EXPONENTIAL = 'Exponential'; |
const TREND_POWER = 'Power'; |
const TREND_POLYNOMIAL_2 = 'Polynomial_2'; |
const TREND_POLYNOMIAL_3 = 'Polynomial_3'; |
const TREND_POLYNOMIAL_4 = 'Polynomial_4'; |
const TREND_POLYNOMIAL_5 = 'Polynomial_5'; |
const TREND_POLYNOMIAL_6 = 'Polynomial_6'; |
const TREND_BEST_FIT = 'Bestfit'; |
const TREND_BEST_FIT_NO_POLY = 'Bestfit_no_Polynomials'; |
|
/** |
* Names of the best-fit trend analysis methods |
* |
* @var string[] |
**/ |
private static $_trendTypes = array( self::TREND_LINEAR, |
self::TREND_LOGARITHMIC, |
self::TREND_EXPONENTIAL, |
self::TREND_POWER |
); |
/** |
* Names of the best-fit trend polynomial orders |
* |
* @var string[] |
**/ |
private static $_trendTypePolyOrders = array( self::TREND_POLYNOMIAL_2, |
self::TREND_POLYNOMIAL_3, |
self::TREND_POLYNOMIAL_4, |
self::TREND_POLYNOMIAL_5, |
self::TREND_POLYNOMIAL_6 |
); |
|
/** |
* Cached results for each method when trying to identify which provides the best fit |
* |
* @var PHPExcel_Best_Fit[] |
**/ |
private static $_trendCache = array(); |
|
|
public static function calculate($trendType=self::TREND_BEST_FIT, $yValues, $xValues=array(), $const=True) { |
// Calculate number of points in each dataset |
$nY = count($yValues); |
$nX = count($xValues); |
|
// Define X Values if necessary |
if ($nX == 0) { |
$xValues = range(1,$nY); |
$nX = $nY; |
} elseif ($nY != $nX) { |
// Ensure both arrays of points are the same size |
trigger_error("trend(): Number of elements in coordinate arrays do not match.", E_USER_ERROR); |
} |
|
$key = md5($trendType.$const.serialize($yValues).serialize($xValues)); |
// Determine which trend method has been requested |
switch ($trendType) { |
// Instantiate and return the class for the requested trend method |
case self::TREND_LINEAR : |
case self::TREND_LOGARITHMIC : |
case self::TREND_EXPONENTIAL : |
case self::TREND_POWER : |
if (!isset(self::$_trendCache[$key])) { |
$className = 'PHPExcel_'.$trendType.'_Best_Fit'; |
self::$_trendCache[$key] = new $className($yValues,$xValues,$const); |
} |
return self::$_trendCache[$key]; |
break; |
case self::TREND_POLYNOMIAL_2 : |
case self::TREND_POLYNOMIAL_3 : |
case self::TREND_POLYNOMIAL_4 : |
case self::TREND_POLYNOMIAL_5 : |
case self::TREND_POLYNOMIAL_6 : |
if (!isset(self::$_trendCache[$key])) { |
$order = substr($trendType,-1); |
self::$_trendCache[$key] = new PHPExcel_Polynomial_Best_Fit($order,$yValues,$xValues,$const); |
} |
return self::$_trendCache[$key]; |
break; |
case self::TREND_BEST_FIT : |
case self::TREND_BEST_FIT_NO_POLY : |
// If the request is to determine the best fit regression, then we test each trend line in turn |
// Start by generating an instance of each available trend method |
foreach(self::$_trendTypes as $trendMethod) { |
$className = 'PHPExcel_'.$trendMethod.'BestFit'; |
$bestFit[$trendMethod] = new $className($yValues,$xValues,$const); |
$bestFitValue[$trendMethod] = $bestFit[$trendMethod]->getGoodnessOfFit(); |
} |
if ($trendType != self::TREND_BEST_FIT_NO_POLY) { |
foreach(self::$_trendTypePolyOrders as $trendMethod) { |
$order = substr($trendMethod,-1); |
$bestFit[$trendMethod] = new PHPExcel_Polynomial_Best_Fit($order,$yValues,$xValues,$const); |
if ($bestFit[$trendMethod]->getError()) { |
unset($bestFit[$trendMethod]); |
} else { |
$bestFitValue[$trendMethod] = $bestFit[$trendMethod]->getGoodnessOfFit(); |
} |
} |
} |
// Determine which of our trend lines is the best fit, and then we return the instance of that trend class |
arsort($bestFitValue); |
$bestFitType = key($bestFitValue); |
return $bestFit[$bestFitType]; |
break; |
default : |
return false; |
} |
} // function calculate() |
|
} // class trendClass |