MATRIX_SINGULAR_EXCEPTION
MATRIX_SINGULAR_EXCEPTION = 'Can only perform operation on singular matrix.'
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.
__construct(\PhpOffice\PhpSpreadsheet\Shared\JAMA\Matrix $A)
LU Decomposition constructor.
\PhpOffice\PhpSpreadsheet\Shared\JAMA\Matrix | $A | Rectangular matrix |
getL() : \PhpOffice\PhpSpreadsheet\Shared\JAMA\Matrix
Get lower triangular factor.
Lower triangular factor
getU() : \PhpOffice\PhpSpreadsheet\Shared\JAMA\Matrix
Get upper triangular factor.
Upper triangular factor
solve(mixed $B) : \PhpOffice\PhpSpreadsheet\Shared\JAMA\Matrix
Solve A*X = B.
mixed | $B | a Matrix with as many rows as A and any number of columns |
illegalArgumentException Matrix row dimensions must agree
runtimeException Matrix is singular
X so that LUX = B(piv,:)
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