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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/dpptrf.c
parent01f64c1ecd0d4ffa9e3a74478335f1745f26cc75 (diff)
downloadydb-90d450f74722da7859d6f510a869f6c6908fd12f.tar.gz
[] add metering mode to CLI
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diff --git a/contrib/libs/clapack/dpptrf.c b/contrib/libs/clapack/dpptrf.c
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+/* dpptrf.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 doublereal c_b16 = -1.;
+
+/* Subroutine */ int dpptrf_(char *uplo, integer *n, doublereal *ap, integer *
+ info)
+{
+ /* System generated locals */
+ integer i__1, i__2;
+ doublereal d__1;
+
+ /* Builtin functions */
+ double sqrt(doublereal);
+
+ /* Local variables */
+ integer j, jc, jj;
+ doublereal ajj;
+ extern doublereal ddot_(integer *, doublereal *, integer *, doublereal *,
+ integer *);
+ extern /* Subroutine */ int dspr_(char *, integer *, doublereal *,
+ doublereal *, integer *, doublereal *), dscal_(integer *,
+ doublereal *, doublereal *, integer *);
+ extern logical lsame_(char *, char *);
+ logical upper;
+ extern /* Subroutine */ int dtpsv_(char *, char *, char *, integer *,
+ doublereal *, doublereal *, integer *),
+ xerbla_(char *, integer *);
+
+
+/* -- LAPACK routine (version 3.2) -- */
+/* Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. */
+/* November 2006 */
+
+/* .. Scalar Arguments .. */
+/* .. */
+/* .. Array Arguments .. */
+/* .. */
+
+/* Purpose */
+/* ======= */
+
+/* DPPTRF computes the Cholesky factorization of a real symmetric */
+/* positive definite matrix A stored in packed format. */
+
+/* The factorization has the form */
+/* A = U**T * U, if UPLO = 'U', or */
+/* A = L * L**T, if UPLO = 'L', */
+/* where U is an upper triangular matrix and L is lower triangular. */
+
+/* Arguments */
+/* ========= */
+
+/* UPLO (input) CHARACTER*1 */
+/* = 'U': Upper triangle of A is stored; */
+/* = 'L': Lower triangle of A is stored. */
+
+/* N (input) INTEGER */
+/* The order of the matrix A. N >= 0. */
+
+/* AP (input/output) DOUBLE PRECISION array, dimension (N*(N+1)/2) */
+/* On entry, the upper or lower triangle of the symmetric matrix */
+/* A, packed columnwise in a linear array. The j-th column of A */
+/* is stored in the array AP as follows: */
+/* if UPLO = 'U', AP(i + (j-1)*j/2) = A(i,j) for 1<=i<=j; */
+/* if UPLO = 'L', AP(i + (j-1)*(2n-j)/2) = A(i,j) for j<=i<=n. */
+/* See below for further details. */
+
+/* On exit, if INFO = 0, the triangular factor U or L from the */
+/* Cholesky factorization A = U**T*U or A = L*L**T, in the same */
+/* storage format as A. */
+
+/* INFO (output) INTEGER */
+/* = 0: successful exit */
+/* < 0: if INFO = -i, the i-th argument had an illegal value */
+/* > 0: if INFO = i, the leading minor of order i is not */
+/* positive definite, and the factorization could not be */
+/* completed. */
+
+/* Further Details */
+/* ======= ======= */
+
+/* The packed storage scheme is illustrated by the following example */
+/* when N = 4, UPLO = 'U': */
+
+/* Two-dimensional storage of the symmetric matrix A: */
+
+/* a11 a12 a13 a14 */
+/* a22 a23 a24 */
+/* a33 a34 (aij = aji) */
+/* a44 */
+
+/* Packed storage of the upper triangle of A: */
+
+/* AP = [ a11, a12, a22, a13, a23, a33, a14, a24, a34, a44 ] */
+
+/* ===================================================================== */
+
+/* .. Parameters .. */
+/* .. */
+/* .. Local Scalars .. */
+/* .. */
+/* .. External Functions .. */
+/* .. */
+/* .. External Subroutines .. */
+/* .. */
+/* .. Intrinsic Functions .. */
+/* .. */
+/* .. Executable Statements .. */
+
+/* Test the input parameters. */
+
+ /* Parameter adjustments */
+ --ap;
+
+ /* Function Body */
+ *info = 0;
+ upper = lsame_(uplo, "U");
+ if (! upper && ! lsame_(uplo, "L")) {
+ *info = -1;
+ } else if (*n < 0) {
+ *info = -2;
+ }
+ if (*info != 0) {
+ i__1 = -(*info);
+ xerbla_("DPPTRF", &i__1);
+ return 0;
+ }
+
+/* Quick return if possible */
+
+ if (*n == 0) {
+ return 0;
+ }
+
+ if (upper) {
+
+/* Compute the Cholesky factorization A = U'*U. */
+
+ jj = 0;
+ i__1 = *n;
+ for (j = 1; j <= i__1; ++j) {
+ jc = jj + 1;
+ jj += j;
+
+/* Compute elements 1:J-1 of column J. */
+
+ if (j > 1) {
+ i__2 = j - 1;
+ dtpsv_("Upper", "Transpose", "Non-unit", &i__2, &ap[1], &ap[
+ jc], &c__1);
+ }
+
+/* Compute U(J,J) and test for non-positive-definiteness. */
+
+ i__2 = j - 1;
+ ajj = ap[jj] - ddot_(&i__2, &ap[jc], &c__1, &ap[jc], &c__1);
+ if (ajj <= 0.) {
+ ap[jj] = ajj;
+ goto L30;
+ }
+ ap[jj] = sqrt(ajj);
+/* L10: */
+ }
+ } else {
+
+/* Compute the Cholesky factorization A = L*L'. */
+
+ jj = 1;
+ i__1 = *n;
+ for (j = 1; j <= i__1; ++j) {
+
+/* Compute L(J,J) and test for non-positive-definiteness. */
+
+ ajj = ap[jj];
+ if (ajj <= 0.) {
+ ap[jj] = ajj;
+ goto L30;
+ }
+ ajj = sqrt(ajj);
+ ap[jj] = ajj;
+
+/* Compute elements J+1:N of column J and update the trailing */
+/* submatrix. */
+
+ if (j < *n) {
+ i__2 = *n - j;
+ d__1 = 1. / ajj;
+ dscal_(&i__2, &d__1, &ap[jj + 1], &c__1);
+ i__2 = *n - j;
+ dspr_("Lower", &i__2, &c_b16, &ap[jj + 1], &c__1, &ap[jj + *n
+ - j + 1]);
+ jj = jj + *n - j + 1;
+ }
+/* L20: */
+ }
+ }
+ goto L40;
+
+L30:
+ *info = j;
+
+L40:
+ return 0;
+
+/* End of DPPTRF */
+
+} /* dpptrf_ */