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		| @ -1,258 +0,0 @@ | ||||
| <?php | ||||
| /** | ||||
|  *	@package JAMA | ||||
|  * | ||||
|  *	For an m-by-n matrix A with m >= n, the LU decomposition is an m-by-n | ||||
|  *	unit lower triangular matrix L, an n-by-n upper triangular matrix U, | ||||
|  *	and a permutation vector piv of length m so that A(piv,:) = L*U. | ||||
|  *	If m < n, then L is m-by-m and U is m-by-n. | ||||
|  * | ||||
|  *	The LU decompostion with pivoting always exists, even if the matrix is | ||||
|  *	singular, so the constructor will never fail. The primary use of the | ||||
|  *	LU decomposition is in the solution of square systems of simultaneous | ||||
|  *	linear equations. This will fail if isNonsingular() returns false. | ||||
|  * | ||||
|  *	@author Paul Meagher | ||||
|  *	@author Bartosz Matosiuk | ||||
|  *	@author Michael Bommarito | ||||
|  *	@version 1.1 | ||||
|  *	@license PHP v3.0 | ||||
|  */ | ||||
| class PHPExcel_Shared_JAMA_LUDecomposition { | ||||
|  | ||||
| 	const MatrixSingularException	= "Can only perform operation on singular matrix."; | ||||
| 	const MatrixSquareException		= "Mismatched Row dimension"; | ||||
|  | ||||
| 	/** | ||||
| 	 *	Decomposition storage | ||||
| 	 *	@var array | ||||
| 	 */ | ||||
| 	private $LU = array(); | ||||
|  | ||||
| 	/** | ||||
| 	 *	Row dimension. | ||||
| 	 *	@var int | ||||
| 	 */ | ||||
| 	private $m; | ||||
|  | ||||
| 	/** | ||||
| 	 *	Column dimension. | ||||
| 	 *	@var int | ||||
| 	 */ | ||||
| 	private $n; | ||||
|  | ||||
| 	/** | ||||
| 	 *	Pivot sign. | ||||
| 	 *	@var int | ||||
| 	 */ | ||||
| 	private $pivsign; | ||||
|  | ||||
| 	/** | ||||
| 	 *	Internal storage of pivot vector. | ||||
| 	 *	@var array | ||||
| 	 */ | ||||
| 	private $piv = array(); | ||||
|  | ||||
|  | ||||
| 	/** | ||||
| 	 *	LU Decomposition constructor. | ||||
| 	 * | ||||
| 	 *	@param $A Rectangular matrix | ||||
| 	 *	@return Structure to access L, U and piv. | ||||
| 	 */ | ||||
| 	public function __construct($A) { | ||||
| 		if ($A instanceof PHPExcel_Shared_JAMA_Matrix) { | ||||
| 			// Use a "left-looking", dot-product, Crout/Doolittle algorithm. | ||||
| 			$this->LU = $A->getArray(); | ||||
| 			$this->m  = $A->getRowDimension(); | ||||
| 			$this->n  = $A->getColumnDimension(); | ||||
| 			for ($i = 0; $i < $this->m; ++$i) { | ||||
| 				$this->piv[$i] = $i; | ||||
| 			} | ||||
| 			$this->pivsign = 1; | ||||
| 			$LUrowi = $LUcolj = array(); | ||||
|  | ||||
| 			// Outer loop. | ||||
| 			for ($j = 0; $j < $this->n; ++$j) { | ||||
| 				// Make a copy of the j-th column to localize references. | ||||
| 				for ($i = 0; $i < $this->m; ++$i) { | ||||
| 					$LUcolj[$i] = &$this->LU[$i][$j]; | ||||
| 				} | ||||
| 				// Apply previous transformations. | ||||
| 				for ($i = 0; $i < $this->m; ++$i) { | ||||
| 					$LUrowi = $this->LU[$i]; | ||||
| 					// Most of the time is spent in the following dot product. | ||||
| 					$kmax = min($i,$j); | ||||
| 					$s = 0.0; | ||||
| 					for ($k = 0; $k < $kmax; ++$k) { | ||||
| 						$s += $LUrowi[$k] * $LUcolj[$k]; | ||||
| 					} | ||||
| 					$LUrowi[$j] = $LUcolj[$i] -= $s; | ||||
| 				} | ||||
| 				// Find pivot and exchange if necessary. | ||||
| 				$p = $j; | ||||
| 				for ($i = $j+1; $i < $this->m; ++$i) { | ||||
| 					if (abs($LUcolj[$i]) > abs($LUcolj[$p])) { | ||||
| 						$p = $i; | ||||
| 					} | ||||
| 				} | ||||
| 				if ($p != $j) { | ||||
| 					for ($k = 0; $k < $this->n; ++$k) { | ||||
| 						$t = $this->LU[$p][$k]; | ||||
| 						$this->LU[$p][$k] = $this->LU[$j][$k]; | ||||
| 						$this->LU[$j][$k] = $t; | ||||
| 					} | ||||
| 					$k = $this->piv[$p]; | ||||
| 					$this->piv[$p] = $this->piv[$j]; | ||||
| 					$this->piv[$j] = $k; | ||||
| 					$this->pivsign = $this->pivsign * -1; | ||||
| 				} | ||||
| 				// Compute multipliers. | ||||
| 				if (($j < $this->m) && ($this->LU[$j][$j] != 0.0)) { | ||||
| 					for ($i = $j+1; $i < $this->m; ++$i) { | ||||
| 						$this->LU[$i][$j] /= $this->LU[$j][$j]; | ||||
| 					} | ||||
| 				} | ||||
| 			} | ||||
| 		} else { | ||||
| 			throw new Exception(PHPExcel_Shared_JAMA_Matrix::ArgumentTypeException); | ||||
| 		} | ||||
| 	}	//	function __construct() | ||||
|  | ||||
|  | ||||
| 	/** | ||||
| 	 *	Get lower triangular factor. | ||||
| 	 * | ||||
| 	 *	@return array Lower triangular factor | ||||
| 	 */ | ||||
| 	public function getL() { | ||||
| 		for ($i = 0; $i < $this->m; ++$i) { | ||||
| 			for ($j = 0; $j < $this->n; ++$j) { | ||||
| 				if ($i > $j) { | ||||
| 					$L[$i][$j] = $this->LU[$i][$j]; | ||||
| 				} elseif ($i == $j) { | ||||
| 					$L[$i][$j] = 1.0; | ||||
| 				} else { | ||||
| 					$L[$i][$j] = 0.0; | ||||
| 				} | ||||
| 			} | ||||
| 		} | ||||
| 		return new PHPExcel_Shared_JAMA_Matrix($L); | ||||
| 	}	//	function getL() | ||||
|  | ||||
|  | ||||
| 	/** | ||||
| 	 *	Get upper triangular factor. | ||||
| 	 * | ||||
| 	 *	@return array Upper triangular factor | ||||
| 	 */ | ||||
| 	public function getU() { | ||||
| 		for ($i = 0; $i < $this->n; ++$i) { | ||||
| 			for ($j = 0; $j < $this->n; ++$j) { | ||||
| 				if ($i <= $j) { | ||||
| 					$U[$i][$j] = $this->LU[$i][$j]; | ||||
| 				} else { | ||||
| 					$U[$i][$j] = 0.0; | ||||
| 				} | ||||
| 			} | ||||
| 		} | ||||
| 		return new PHPExcel_Shared_JAMA_Matrix($U); | ||||
| 	}	//	function getU() | ||||
|  | ||||
|  | ||||
| 	/** | ||||
| 	 *	Return pivot permutation vector. | ||||
| 	 * | ||||
| 	 *	@return array Pivot vector | ||||
| 	 */ | ||||
| 	public function getPivot() { | ||||
| 		return $this->piv; | ||||
| 	}	//	function getPivot() | ||||
|  | ||||
|  | ||||
| 	/** | ||||
| 	 *	Alias for getPivot | ||||
| 	 * | ||||
| 	 *	@see getPivot | ||||
| 	 */ | ||||
| 	public function getDoublePivot() { | ||||
| 		return $this->getPivot(); | ||||
| 	}	//	function getDoublePivot() | ||||
|  | ||||
|  | ||||
| 	/** | ||||
| 	 *	Is the matrix nonsingular? | ||||
| 	 * | ||||
| 	 *	@return true if U, and hence A, is nonsingular. | ||||
| 	 */ | ||||
| 	public function isNonsingular() { | ||||
| 		for ($j = 0; $j < $this->n; ++$j) { | ||||
| 			if ($this->LU[$j][$j] == 0) { | ||||
| 				return false; | ||||
| 			} | ||||
| 		} | ||||
| 		return true; | ||||
| 	}	//	function isNonsingular() | ||||
|  | ||||
|  | ||||
| 	/** | ||||
| 	 *	Count determinants | ||||
| 	 * | ||||
| 	 *	@return array d matrix deterninat | ||||
| 	 */ | ||||
| 	public function det() { | ||||
| 		if ($this->m == $this->n) { | ||||
| 			$d = $this->pivsign; | ||||
| 			for ($j = 0; $j < $this->n; ++$j) { | ||||
| 				$d *= $this->LU[$j][$j]; | ||||
| 			} | ||||
| 			return $d; | ||||
| 		} else { | ||||
| 			throw new Exception(PHPExcel_Shared_JAMA_Matrix::MatrixDimensionException); | ||||
| 		} | ||||
| 	}	//	function det() | ||||
|  | ||||
|  | ||||
| 	/** | ||||
| 	 *	Solve A*X = B | ||||
| 	 * | ||||
| 	 *	@param  $B  A Matrix with as many rows as A and any number of columns. | ||||
| 	 *	@return  X so that L*U*X = B(piv,:) | ||||
| 	 *	@exception  IllegalArgumentException Matrix row dimensions must agree. | ||||
| 	 *	@exception  RuntimeException  Matrix is singular. | ||||
| 	 */ | ||||
| 	public function solve($B) { | ||||
| 		if ($B->getRowDimension() == $this->m) { | ||||
| 			if ($this->isNonsingular()) { | ||||
| 				// Copy right hand side with pivoting | ||||
| 				$nx = $B->getColumnDimension(); | ||||
| 				$X  = $B->getMatrix($this->piv, 0, $nx-1); | ||||
| 				// Solve L*Y = B(piv,:) | ||||
| 				for ($k = 0; $k < $this->n; ++$k) { | ||||
| 					for ($i = $k+1; $i < $this->n; ++$i) { | ||||
| 						for ($j = 0; $j < $nx; ++$j) { | ||||
| 							$X->A[$i][$j] -= $X->A[$k][$j] * $this->LU[$i][$k]; | ||||
| 						} | ||||
| 					} | ||||
| 				} | ||||
| 				// Solve U*X = Y; | ||||
| 				for ($k = $this->n-1; $k >= 0; --$k) { | ||||
| 					for ($j = 0; $j < $nx; ++$j) { | ||||
| 						$X->A[$k][$j] /= $this->LU[$k][$k]; | ||||
| 					} | ||||
| 					for ($i = 0; $i < $k; ++$i) { | ||||
| 						for ($j = 0; $j < $nx; ++$j) { | ||||
| 							$X->A[$i][$j] -= $X->A[$k][$j] * $this->LU[$i][$k]; | ||||
| 						} | ||||
| 					} | ||||
| 				} | ||||
| 				return $X; | ||||
| 			} else { | ||||
| 				throw new Exception(self::MatrixSingularException); | ||||
| 			} | ||||
| 		} else { | ||||
| 			throw new Exception(self::MatrixSquareException); | ||||
| 		} | ||||
| 	}	//	function solve() | ||||
|  | ||||
| }	//	class PHPExcel_Shared_JAMA_LUDecomposition | ||||
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