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author | shmel1k <shmel1k@ydb.tech> | 2022-09-02 12:44:59 +0300 |
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committer | shmel1k <shmel1k@ydb.tech> | 2022-09-02 12:44:59 +0300 |
commit | 90d450f74722da7859d6f510a869f6c6908fd12f (patch) | |
tree | 538c718dedc76cdfe37ad6d01ff250dd930d9278 /contrib/libs/clapack/sgetf2.c | |
parent | 01f64c1ecd0d4ffa9e3a74478335f1745f26cc75 (diff) | |
download | ydb-90d450f74722da7859d6f510a869f6c6908fd12f.tar.gz |
[] add metering mode to CLI
Diffstat (limited to 'contrib/libs/clapack/sgetf2.c')
-rw-r--r-- | contrib/libs/clapack/sgetf2.c | 192 |
1 files changed, 192 insertions, 0 deletions
diff --git a/contrib/libs/clapack/sgetf2.c b/contrib/libs/clapack/sgetf2.c new file mode 100644 index 0000000000..a8393fb2bc --- /dev/null +++ b/contrib/libs/clapack/sgetf2.c @@ -0,0 +1,192 @@ +/* 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_ */ |