sgetrf.f man page
subroutine sgetrf (M, N, A, LDA, IPIV, INFO)
subroutine sgetrf (integerM, integerN, real, dimension( lda, * )A, integerLDA, integer, dimension( * )IPIV, integerINFO)
SGETRF computes an LU factorization of a general M-by-N matrix A using partial pivoting with row interchanges. The factorization has the form A = P * L * U where P is a permutation matrix, L is lower triangular with unit diagonal elements (lower trapezoidal if m > n), and U is upper triangular (upper trapezoidal if m < n). This is the right-looking Level 3 BLAS version of the algorithm.
M is INTEGER The number of rows of the matrix A. M >= 0.
N is INTEGER The number of columns of the matrix A. N >= 0.
A is REAL array, dimension (LDA,N) On entry, the M-by-N matrix to be factored. On exit, the factors L and U from the factorization A = P*L*U; the unit diagonal elements of L are not stored.
LDA is INTEGER The leading dimension of the array A. LDA >= max(1,M).
IPIV is INTEGER array, dimension (min(M,N)) The pivot indices; for 1 <= i <= min(M,N), row i of the matrix was interchanged with row IPIV(i).
INFO is INTEGER = 0: successful exit < 0: if INFO = -i, the i-th argument had an illegal value > 0: if INFO = i, U(i,i) is exactly zero. The factorization has been completed, but the factor U is exactly singular, and division by zero will occur if it is used to solve a system of equations.
Univ. of Tennessee
Univ. of California Berkeley
Univ. of Colorado Denver
Definition at line 109 of file sgetrf.f.
Generated automatically by Doxygen for LAPACK from the source code.
sgetrf(3) is an alias of sgetrf.f(3).