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---
:name: dgetc2
:md5sum: 8407e50951ea8e41f50aa9499510d542
:category: :subroutine
:arguments:
- n:
:type: integer
:intent: input
- a:
:type: doublereal
:intent: input/output
:dims:
- lda
- n
- lda:
:type: integer
:intent: input
- ipiv:
:type: integer
:intent: output
:dims:
- n
- jpiv:
:type: integer
:intent: output
:dims:
- n
- info:
:type: integer
:intent: output
:substitutions: {}
:fortran_help: " SUBROUTINE DGETC2( N, A, LDA, IPIV, JPIV, INFO )\n\n\
* Purpose\n\
* =======\n\
*\n\
* DGETC2 computes an LU factorization with complete pivoting of the\n\
* n-by-n matrix A. The factorization has the form A = P * L * U * Q,\n\
* where P and Q are permutation matrices, L is lower triangular with\n\
* unit diagonal elements and U is upper triangular.\n\
*\n\
* This is the Level 2 BLAS algorithm.\n\
*\n\n\
* Arguments\n\
* =========\n\
*\n\
* N (input) INTEGER\n\
* The order of the matrix A. N >= 0.\n\
*\n\
* A (input/output) DOUBLE PRECISION array, dimension (LDA, N)\n\
* On entry, the n-by-n matrix A to be factored.\n\
* On exit, the factors L and U from the factorization\n\
* A = P*L*U*Q; the unit diagonal elements of L are not stored.\n\
* If U(k, k) appears to be less than SMIN, U(k, k) is given the\n\
* value of SMIN, i.e., giving a nonsingular perturbed system.\n\
*\n\
* LDA (input) INTEGER\n\
* The leading dimension of the array A. LDA >= max(1,N).\n\
*\n\
* IPIV (output) INTEGER array, dimension(N).\n\
* The pivot indices; for 1 <= i <= N, row i of the\n\
* matrix has been interchanged with row IPIV(i).\n\
*\n\
* JPIV (output) INTEGER array, dimension(N).\n\
* The pivot indices; for 1 <= j <= N, column j of the\n\
* matrix has been interchanged with column JPIV(j).\n\
*\n\
* INFO (output) INTEGER\n\
* = 0: successful exit\n\
* > 0: if INFO = k, U(k, k) is likely to produce owerflow if\n\
* we try to solve for x in Ax = b. So U is perturbed to\n\
* avoid the overflow.\n\
*\n\n\
* Further Details\n\
* ===============\n\
*\n\
* Based on contributions by\n\
* Bo Kagstrom and Peter Poromaa, Department of Computing Science,\n\
* Umea University, S-901 87 Umea, Sweden.\n\
*\n\
* =====================================================================\n\
*\n"
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