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authorshmel1k <shmel1k@ydb.tech>2022-09-02 12:44:59 +0300
committershmel1k <shmel1k@ydb.tech>2022-09-02 12:44:59 +0300
commit90d450f74722da7859d6f510a869f6c6908fd12f (patch)
tree538c718dedc76cdfe37ad6d01ff250dd930d9278 /contrib/libs/clapack/sgetf2.c
parent01f64c1ecd0d4ffa9e3a74478335f1745f26cc75 (diff)
downloadydb-90d450f74722da7859d6f510a869f6c6908fd12f.tar.gz
[] add metering mode to CLI
Diffstat (limited to 'contrib/libs/clapack/sgetf2.c')
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diff --git a/contrib/libs/clapack/sgetf2.c b/contrib/libs/clapack/sgetf2.c
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+/* sgetf2.f -- translated by f2c (version 20061008).
+ You must link the resulting object file with libf2c:
+ on Microsoft Windows system, link with libf2c.lib;
+ on Linux or Unix systems, link with .../path/to/libf2c.a -lm
+ or, if you install libf2c.a in a standard place, with -lf2c -lm
+ -- in that order, at the end of the command line, as in
+ cc *.o -lf2c -lm
+ Source for libf2c is in /netlib/f2c/libf2c.zip, e.g.,
+
+ http://www.netlib.org/f2c/libf2c.zip
+*/
+
+#include "f2c.h"
+#include "blaswrap.h"
+
+/* Table of constant values */
+
+static integer c__1 = 1;
+static real c_b8 = -1.f;
+
+/* Subroutine */ int sgetf2_(integer *m, integer *n, real *a, integer *lda,
+ integer *ipiv, integer *info)
+{
+ /* System generated locals */
+ integer a_dim1, a_offset, i__1, i__2, i__3;
+ real r__1;
+
+ /* Local variables */
+ integer i__, j, jp;
+ extern /* Subroutine */ int sger_(integer *, integer *, real *, real *,
+ integer *, real *, integer *, real *, integer *), sscal_(integer *
+, real *, real *, integer *);
+ real sfmin;
+ extern /* Subroutine */ int sswap_(integer *, real *, integer *, real *,
+ integer *);
+ extern doublereal slamch_(char *);
+ extern /* Subroutine */ int xerbla_(char *, integer *);
+ extern integer isamax_(integer *, real *, integer *);
+
+
+/* -- LAPACK routine (version 3.2) -- */
+/* Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. */
+/* November 2006 */
+
+/* .. Scalar Arguments .. */
+/* .. */
+/* .. Array Arguments .. */
+/* .. */
+
+/* Purpose */
+/* ======= */
+
+/* SGETF2 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 2 BLAS version of the algorithm. */
+
+/* Arguments */
+/* ========= */
+
+/* M (input) INTEGER */
+/* The number of rows of the matrix A. M >= 0. */
+
+/* N (input) INTEGER */
+/* The number of columns of the matrix A. N >= 0. */
+
+/* A (input/output) 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 (input) INTEGER */
+/* The leading dimension of the array A. LDA >= max(1,M). */
+
+/* IPIV (output) 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 (output) INTEGER */
+/* = 0: successful exit */
+/* < 0: if INFO = -k, the k-th argument had an illegal value */
+/* > 0: if INFO = k, U(k,k) 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. */
+
+/* ===================================================================== */
+
+/* .. Parameters .. */
+/* .. */
+/* .. Local Scalars .. */
+/* .. */
+/* .. External Functions .. */
+/* .. */
+/* .. External Subroutines .. */
+/* .. */
+/* .. Intrinsic Functions .. */
+/* .. */
+/* .. Executable Statements .. */
+
+/* Test the input parameters. */
+
+ /* Parameter adjustments */
+ a_dim1 = *lda;
+ a_offset = 1 + a_dim1;
+ a -= a_offset;
+ --ipiv;
+
+ /* Function Body */
+ *info = 0;
+ if (*m < 0) {
+ *info = -1;
+ } else if (*n < 0) {
+ *info = -2;
+ } else if (*lda < max(1,*m)) {
+ *info = -4;
+ }
+ if (*info != 0) {
+ i__1 = -(*info);
+ xerbla_("SGETF2", &i__1);
+ return 0;
+ }
+
+/* Quick return if possible */
+
+ if (*m == 0 || *n == 0) {
+ return 0;
+ }
+
+/* Compute machine safe minimum */
+
+ sfmin = slamch_("S");
+
+ i__1 = min(*m,*n);
+ for (j = 1; j <= i__1; ++j) {
+
+/* Find pivot and test for singularity. */
+
+ i__2 = *m - j + 1;
+ jp = j - 1 + isamax_(&i__2, &a[j + j * a_dim1], &c__1);
+ ipiv[j] = jp;
+ if (a[jp + j * a_dim1] != 0.f) {
+
+/* Apply the interchange to columns 1:N. */
+
+ if (jp != j) {
+ sswap_(n, &a[j + a_dim1], lda, &a[jp + a_dim1], lda);
+ }
+
+/* Compute elements J+1:M of J-th column. */
+
+ if (j < *m) {
+ if ((r__1 = a[j + j * a_dim1], dabs(r__1)) >= sfmin) {
+ i__2 = *m - j;
+ r__1 = 1.f / a[j + j * a_dim1];
+ sscal_(&i__2, &r__1, &a[j + 1 + j * a_dim1], &c__1);
+ } else {
+ i__2 = *m - j;
+ for (i__ = 1; i__ <= i__2; ++i__) {
+ a[j + i__ + j * a_dim1] /= a[j + j * a_dim1];
+/* L20: */
+ }
+ }
+ }
+
+ } else if (*info == 0) {
+
+ *info = j;
+ }
+
+ if (j < min(*m,*n)) {
+
+/* Update trailing submatrix. */
+
+ i__2 = *m - j;
+ i__3 = *n - j;
+ sger_(&i__2, &i__3, &c_b8, &a[j + 1 + j * a_dim1], &c__1, &a[j + (
+ j + 1) * a_dim1], lda, &a[j + 1 + (j + 1) * a_dim1], lda);
+ }
+/* L10: */
+ }
+ return 0;
+
+/* End of SGETF2 */
+
+} /* sgetf2_ */