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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/chetd2.c
parent01f64c1ecd0d4ffa9e3a74478335f1745f26cc75 (diff)
downloadydb-90d450f74722da7859d6f510a869f6c6908fd12f.tar.gz
[] add metering mode to CLI
Diffstat (limited to 'contrib/libs/clapack/chetd2.c')
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diff --git a/contrib/libs/clapack/chetd2.c b/contrib/libs/clapack/chetd2.c
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+/* chetd2.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 complex c_b2 = {0.f,0.f};
+static integer c__1 = 1;
+
+/* Subroutine */ int chetd2_(char *uplo, integer *n, complex *a, integer *lda,
+ real *d__, real *e, complex *tau, integer *info)
+{
+ /* System generated locals */
+ integer a_dim1, a_offset, i__1, i__2, i__3;
+ real r__1;
+ complex q__1, q__2, q__3, q__4;
+
+ /* Local variables */
+ integer i__;
+ complex taui;
+ extern /* Subroutine */ int cher2_(char *, integer *, complex *, complex *
+, integer *, complex *, integer *, complex *, integer *);
+ complex alpha;
+ extern /* Complex */ VOID cdotc_(complex *, integer *, complex *, integer
+ *, complex *, integer *);
+ extern logical lsame_(char *, char *);
+ extern /* Subroutine */ int chemv_(char *, integer *, complex *, complex *
+, integer *, complex *, integer *, complex *, complex *, integer *
+), caxpy_(integer *, complex *, complex *, integer *,
+ complex *, integer *);
+ logical upper;
+ extern /* Subroutine */ int clarfg_(integer *, complex *, complex *,
+ integer *, complex *), 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 */
+/* ======= */
+
+/* CHETD2 reduces a complex Hermitian matrix A to real symmetric */
+/* tridiagonal form T by a unitary similarity transformation: */
+/* Q' * A * Q = T. */
+
+/* Arguments */
+/* ========= */
+
+/* UPLO (input) CHARACTER*1 */
+/* Specifies whether the upper or lower triangular part of the */
+/* Hermitian matrix A is stored: */
+/* = 'U': Upper triangular */
+/* = 'L': Lower triangular */
+
+/* N (input) INTEGER */
+/* The order of the matrix A. N >= 0. */
+
+/* A (input/output) COMPLEX array, dimension (LDA,N) */
+/* On entry, the Hermitian matrix A. If UPLO = 'U', the leading */
+/* n-by-n upper triangular part of A contains the upper */
+/* triangular part of the matrix A, and the strictly lower */
+/* triangular part of A is not referenced. If UPLO = 'L', the */
+/* leading n-by-n lower triangular part of A contains the lower */
+/* triangular part of the matrix A, and the strictly upper */
+/* triangular part of A is not referenced. */
+/* On exit, if UPLO = 'U', the diagonal and first superdiagonal */
+/* of A are overwritten by the corresponding elements of the */
+/* tridiagonal matrix T, and the elements above the first */
+/* superdiagonal, with the array TAU, represent the unitary */
+/* matrix Q as a product of elementary reflectors; if UPLO */
+/* = 'L', the diagonal and first subdiagonal of A are over- */
+/* written by the corresponding elements of the tridiagonal */
+/* matrix T, and the elements below the first subdiagonal, with */
+/* the array TAU, represent the unitary matrix Q as a product */
+/* of elementary reflectors. See Further Details. */
+
+/* LDA (input) INTEGER */
+/* The leading dimension of the array A. LDA >= max(1,N). */
+
+/* D (output) REAL array, dimension (N) */
+/* The diagonal elements of the tridiagonal matrix T: */
+/* D(i) = A(i,i). */
+
+/* E (output) REAL array, dimension (N-1) */
+/* The off-diagonal elements of the tridiagonal matrix T: */
+/* E(i) = A(i,i+1) if UPLO = 'U', E(i) = A(i+1,i) if UPLO = 'L'. */
+
+/* TAU (output) COMPLEX array, dimension (N-1) */
+/* The scalar factors of the elementary reflectors (see Further */
+/* Details). */
+
+/* INFO (output) INTEGER */
+/* = 0: successful exit */
+/* < 0: if INFO = -i, the i-th argument had an illegal value. */
+
+/* Further Details */
+/* =============== */
+
+/* If UPLO = 'U', the matrix Q is represented as a product of elementary */
+/* reflectors */
+
+/* Q = H(n-1) . . . H(2) H(1). */
+
+/* Each H(i) has the form */
+
+/* H(i) = I - tau * v * v' */
+
+/* where tau is a complex scalar, and v is a complex vector with */
+/* v(i+1:n) = 0 and v(i) = 1; v(1:i-1) is stored on exit in */
+/* A(1:i-1,i+1), and tau in TAU(i). */
+
+/* If UPLO = 'L', the matrix Q is represented as a product of elementary */
+/* reflectors */
+
+/* Q = H(1) H(2) . . . H(n-1). */
+
+/* Each H(i) has the form */
+
+/* H(i) = I - tau * v * v' */
+
+/* where tau is a complex scalar, and v is a complex vector with */
+/* v(1:i) = 0 and v(i+1) = 1; v(i+2:n) is stored on exit in A(i+2:n,i), */
+/* and tau in TAU(i). */
+
+/* The contents of A on exit are illustrated by the following examples */
+/* with n = 5: */
+
+/* if UPLO = 'U': if UPLO = 'L': */
+
+/* ( d e v2 v3 v4 ) ( d ) */
+/* ( d e v3 v4 ) ( e d ) */
+/* ( d e v4 ) ( v1 e d ) */
+/* ( d e ) ( v1 v2 e d ) */
+/* ( d ) ( v1 v2 v3 e d ) */
+
+/* where d and e denote diagonal and off-diagonal elements of T, and vi */
+/* denotes an element of the vector defining H(i). */
+
+/* ===================================================================== */
+
+/* .. Parameters .. */
+/* .. */
+/* .. Local Scalars .. */
+/* .. */
+/* .. External Subroutines .. */
+/* .. */
+/* .. External Functions .. */
+/* .. */
+/* .. Intrinsic Functions .. */
+/* .. */
+/* .. Executable Statements .. */
+
+/* Test the input parameters */
+
+ /* Parameter adjustments */
+ a_dim1 = *lda;
+ a_offset = 1 + a_dim1;
+ a -= a_offset;
+ --d__;
+ --e;
+ --tau;
+
+ /* Function Body */
+ *info = 0;
+ upper = lsame_(uplo, "U");
+ if (! upper && ! lsame_(uplo, "L")) {
+ *info = -1;
+ } else if (*n < 0) {
+ *info = -2;
+ } else if (*lda < max(1,*n)) {
+ *info = -4;
+ }
+ if (*info != 0) {
+ i__1 = -(*info);
+ xerbla_("CHETD2", &i__1);
+ return 0;
+ }
+
+/* Quick return if possible */
+
+ if (*n <= 0) {
+ return 0;
+ }
+
+ if (upper) {
+
+/* Reduce the upper triangle of A */
+
+ i__1 = *n + *n * a_dim1;
+ i__2 = *n + *n * a_dim1;
+ r__1 = a[i__2].r;
+ a[i__1].r = r__1, a[i__1].i = 0.f;
+ for (i__ = *n - 1; i__ >= 1; --i__) {
+
+/* Generate elementary reflector H(i) = I - tau * v * v' */
+/* to annihilate A(1:i-1,i+1) */
+
+ i__1 = i__ + (i__ + 1) * a_dim1;
+ alpha.r = a[i__1].r, alpha.i = a[i__1].i;
+ clarfg_(&i__, &alpha, &a[(i__ + 1) * a_dim1 + 1], &c__1, &taui);
+ i__1 = i__;
+ e[i__1] = alpha.r;
+
+ if (taui.r != 0.f || taui.i != 0.f) {
+
+/* Apply H(i) from both sides to A(1:i,1:i) */
+
+ i__1 = i__ + (i__ + 1) * a_dim1;
+ a[i__1].r = 1.f, a[i__1].i = 0.f;
+
+/* Compute x := tau * A * v storing x in TAU(1:i) */
+
+ chemv_(uplo, &i__, &taui, &a[a_offset], lda, &a[(i__ + 1) *
+ a_dim1 + 1], &c__1, &c_b2, &tau[1], &c__1);
+
+/* Compute w := x - 1/2 * tau * (x'*v) * v */
+
+ q__3.r = -.5f, q__3.i = -0.f;
+ q__2.r = q__3.r * taui.r - q__3.i * taui.i, q__2.i = q__3.r *
+ taui.i + q__3.i * taui.r;
+ cdotc_(&q__4, &i__, &tau[1], &c__1, &a[(i__ + 1) * a_dim1 + 1]
+, &c__1);
+ q__1.r = q__2.r * q__4.r - q__2.i * q__4.i, q__1.i = q__2.r *
+ q__4.i + q__2.i * q__4.r;
+ alpha.r = q__1.r, alpha.i = q__1.i;
+ caxpy_(&i__, &alpha, &a[(i__ + 1) * a_dim1 + 1], &c__1, &tau[
+ 1], &c__1);
+
+/* Apply the transformation as a rank-2 update: */
+/* A := A - v * w' - w * v' */
+
+ q__1.r = -1.f, q__1.i = -0.f;
+ cher2_(uplo, &i__, &q__1, &a[(i__ + 1) * a_dim1 + 1], &c__1, &
+ tau[1], &c__1, &a[a_offset], lda);
+
+ } else {
+ i__1 = i__ + i__ * a_dim1;
+ i__2 = i__ + i__ * a_dim1;
+ r__1 = a[i__2].r;
+ a[i__1].r = r__1, a[i__1].i = 0.f;
+ }
+ i__1 = i__ + (i__ + 1) * a_dim1;
+ i__2 = i__;
+ a[i__1].r = e[i__2], a[i__1].i = 0.f;
+ i__1 = i__ + 1;
+ i__2 = i__ + 1 + (i__ + 1) * a_dim1;
+ d__[i__1] = a[i__2].r;
+ i__1 = i__;
+ tau[i__1].r = taui.r, tau[i__1].i = taui.i;
+/* L10: */
+ }
+ i__1 = a_dim1 + 1;
+ d__[1] = a[i__1].r;
+ } else {
+
+/* Reduce the lower triangle of A */
+
+ i__1 = a_dim1 + 1;
+ i__2 = a_dim1 + 1;
+ r__1 = a[i__2].r;
+ a[i__1].r = r__1, a[i__1].i = 0.f;
+ i__1 = *n - 1;
+ for (i__ = 1; i__ <= i__1; ++i__) {
+
+/* Generate elementary reflector H(i) = I - tau * v * v' */
+/* to annihilate A(i+2:n,i) */
+
+ i__2 = i__ + 1 + i__ * a_dim1;
+ alpha.r = a[i__2].r, alpha.i = a[i__2].i;
+ i__2 = *n - i__;
+/* Computing MIN */
+ i__3 = i__ + 2;
+ clarfg_(&i__2, &alpha, &a[min(i__3, *n)+ i__ * a_dim1], &c__1, &
+ taui);
+ i__2 = i__;
+ e[i__2] = alpha.r;
+
+ if (taui.r != 0.f || taui.i != 0.f) {
+
+/* Apply H(i) from both sides to A(i+1:n,i+1:n) */
+
+ i__2 = i__ + 1 + i__ * a_dim1;
+ a[i__2].r = 1.f, a[i__2].i = 0.f;
+
+/* Compute x := tau * A * v storing y in TAU(i:n-1) */
+
+ i__2 = *n - i__;
+ chemv_(uplo, &i__2, &taui, &a[i__ + 1 + (i__ + 1) * a_dim1],
+ lda, &a[i__ + 1 + i__ * a_dim1], &c__1, &c_b2, &tau[
+ i__], &c__1);
+
+/* Compute w := x - 1/2 * tau * (x'*v) * v */
+
+ q__3.r = -.5f, q__3.i = -0.f;
+ q__2.r = q__3.r * taui.r - q__3.i * taui.i, q__2.i = q__3.r *
+ taui.i + q__3.i * taui.r;
+ i__2 = *n - i__;
+ cdotc_(&q__4, &i__2, &tau[i__], &c__1, &a[i__ + 1 + i__ *
+ a_dim1], &c__1);
+ q__1.r = q__2.r * q__4.r - q__2.i * q__4.i, q__1.i = q__2.r *
+ q__4.i + q__2.i * q__4.r;
+ alpha.r = q__1.r, alpha.i = q__1.i;
+ i__2 = *n - i__;
+ caxpy_(&i__2, &alpha, &a[i__ + 1 + i__ * a_dim1], &c__1, &tau[
+ i__], &c__1);
+
+/* Apply the transformation as a rank-2 update: */
+/* A := A - v * w' - w * v' */
+
+ i__2 = *n - i__;
+ q__1.r = -1.f, q__1.i = -0.f;
+ cher2_(uplo, &i__2, &q__1, &a[i__ + 1 + i__ * a_dim1], &c__1,
+ &tau[i__], &c__1, &a[i__ + 1 + (i__ + 1) * a_dim1],
+ lda);
+
+ } else {
+ i__2 = i__ + 1 + (i__ + 1) * a_dim1;
+ i__3 = i__ + 1 + (i__ + 1) * a_dim1;
+ r__1 = a[i__3].r;
+ a[i__2].r = r__1, a[i__2].i = 0.f;
+ }
+ i__2 = i__ + 1 + i__ * a_dim1;
+ i__3 = i__;
+ a[i__2].r = e[i__3], a[i__2].i = 0.f;
+ i__2 = i__;
+ i__3 = i__ + i__ * a_dim1;
+ d__[i__2] = a[i__3].r;
+ i__2 = i__;
+ tau[i__2].r = taui.r, tau[i__2].i = taui.i;
+/* L20: */
+ }
+ i__1 = *n;
+ i__2 = *n + *n * a_dim1;
+ d__[i__1] = a[i__2].r;
+ }
+
+ return 0;
+
+/* End of CHETD2 */
+
+} /* chetd2_ */