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---
:name: sgetf2
:md5sum: 6afacce566d20b4c1f8a8014c205bd97
:category: :subroutine
:arguments:
- m:
:type: integer
:intent: input
- n:
:type: integer
:intent: input
- a:
:type: real
:intent: input/output
:dims:
- lda
- n
- lda:
:type: integer
:intent: input
- ipiv:
:type: integer
:intent: output
:dims:
- MIN(m,n)
- info:
:type: integer
:intent: output
:substitutions: {}
:fortran_help: " SUBROUTINE SGETF2( M, N, A, LDA, IPIV, INFO )\n\n\
* Purpose\n\
* =======\n\
*\n\
* SGETF2 computes an LU factorization of a general m-by-n matrix A\n\
* using partial pivoting with row interchanges.\n\
*\n\
* The factorization has the form\n\
* A = P * L * U\n\
* where P is a permutation matrix, L is lower triangular with unit\n\
* diagonal elements (lower trapezoidal if m > n), and U is upper\n\
* triangular (upper trapezoidal if m < n).\n\
*\n\
* This is the right-looking Level 2 BLAS version of the algorithm.\n\
*\n\n\
* Arguments\n\
* =========\n\
*\n\
* M (input) INTEGER\n\
* The number of rows of the matrix A. M >= 0.\n\
*\n\
* N (input) INTEGER\n\
* The number of columns of the matrix A. N >= 0.\n\
*\n\
* A (input/output) REAL array, dimension (LDA,N)\n\
* On entry, the m by n matrix to be factored.\n\
* On exit, the factors L and U from the factorization\n\
* A = P*L*U; the unit diagonal elements of L are not stored.\n\
*\n\
* LDA (input) INTEGER\n\
* The leading dimension of the array A. LDA >= max(1,M).\n\
*\n\
* IPIV (output) INTEGER array, dimension (min(M,N))\n\
* The pivot indices; for 1 <= i <= min(M,N), row i of the\n\
* matrix was interchanged with row IPIV(i).\n\
*\n\
* INFO (output) INTEGER\n\
* = 0: successful exit\n\
* < 0: if INFO = -k, the k-th argument had an illegal value\n\
* > 0: if INFO = k, U(k,k) is exactly zero. The factorization\n\
* has been completed, but the factor U is exactly\n\
* singular, and division by zero will occur if it is used\n\
* to solve a system of equations.\n\
*\n\n\
* =====================================================================\n\
*\n"
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