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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/sgtrfs.c
parent01f64c1ecd0d4ffa9e3a74478335f1745f26cc75 (diff)
downloadydb-90d450f74722da7859d6f510a869f6c6908fd12f.tar.gz
[] add metering mode to CLI
Diffstat (limited to 'contrib/libs/clapack/sgtrfs.c')
-rw-r--r--contrib/libs/clapack/sgtrfs.c444
1 files changed, 444 insertions, 0 deletions
diff --git a/contrib/libs/clapack/sgtrfs.c b/contrib/libs/clapack/sgtrfs.c
new file mode 100644
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+++ b/contrib/libs/clapack/sgtrfs.c
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+/* sgtrfs.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_b18 = -1.f;
+static real c_b19 = 1.f;
+
+/* Subroutine */ int sgtrfs_(char *trans, integer *n, integer *nrhs, real *dl,
+ real *d__, real *du, real *dlf, real *df, real *duf, real *du2,
+ integer *ipiv, real *b, integer *ldb, real *x, integer *ldx, real *
+ ferr, real *berr, real *work, integer *iwork, integer *info)
+{
+ /* System generated locals */
+ integer b_dim1, b_offset, x_dim1, x_offset, i__1, i__2;
+ real r__1, r__2, r__3, r__4;
+
+ /* Local variables */
+ integer i__, j;
+ real s;
+ integer nz;
+ real eps;
+ integer kase;
+ real safe1, safe2;
+ extern logical lsame_(char *, char *);
+ integer isave[3], count;
+ extern /* Subroutine */ int scopy_(integer *, real *, integer *, real *,
+ integer *), saxpy_(integer *, real *, real *, integer *, real *,
+ integer *), slacn2_(integer *, real *, real *, integer *, real *,
+ integer *, integer *);
+ extern doublereal slamch_(char *);
+ real safmin;
+ extern /* Subroutine */ int xerbla_(char *, integer *), slagtm_(
+ char *, integer *, integer *, real *, real *, real *, real *,
+ real *, integer *, real *, real *, integer *);
+ logical notran;
+ char transn[1], transt[1];
+ real lstres;
+ extern /* Subroutine */ int sgttrs_(char *, integer *, integer *, real *,
+ real *, real *, real *, integer *, real *, integer *, integer *);
+
+
+/* -- LAPACK routine (version 3.2) -- */
+/* Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. */
+/* November 2006 */
+
+/* Modified to call SLACN2 in place of SLACON, 7 Feb 03, SJH. */
+
+/* .. Scalar Arguments .. */
+/* .. */
+/* .. Array Arguments .. */
+/* .. */
+
+/* Purpose */
+/* ======= */
+
+/* SGTRFS improves the computed solution to a system of linear */
+/* equations when the coefficient matrix is tridiagonal, and provides */
+/* error bounds and backward error estimates for the solution. */
+
+/* Arguments */
+/* ========= */
+
+/* TRANS (input) CHARACTER*1 */
+/* Specifies the form of the system of equations: */
+/* = 'N': A * X = B (No transpose) */
+/* = 'T': A**T * X = B (Transpose) */
+/* = 'C': A**H * X = B (Conjugate transpose = Transpose) */
+
+/* N (input) INTEGER */
+/* The order of the matrix A. N >= 0. */
+
+/* NRHS (input) INTEGER */
+/* The number of right hand sides, i.e., the number of columns */
+/* of the matrix B. NRHS >= 0. */
+
+/* DL (input) REAL array, dimension (N-1) */
+/* The (n-1) subdiagonal elements of A. */
+
+/* D (input) REAL array, dimension (N) */
+/* The diagonal elements of A. */
+
+/* DU (input) REAL array, dimension (N-1) */
+/* The (n-1) superdiagonal elements of A. */
+
+/* DLF (input) REAL array, dimension (N-1) */
+/* The (n-1) multipliers that define the matrix L from the */
+/* LU factorization of A as computed by SGTTRF. */
+
+/* DF (input) REAL array, dimension (N) */
+/* The n diagonal elements of the upper triangular matrix U from */
+/* the LU factorization of A. */
+
+/* DUF (input) REAL array, dimension (N-1) */
+/* The (n-1) elements of the first superdiagonal of U. */
+
+/* DU2 (input) REAL array, dimension (N-2) */
+/* The (n-2) elements of the second superdiagonal of U. */
+
+/* IPIV (input) INTEGER array, dimension (N) */
+/* The pivot indices; for 1 <= i <= n, row i of the matrix was */
+/* interchanged with row IPIV(i). IPIV(i) will always be either */
+/* i or i+1; IPIV(i) = i indicates a row interchange was not */
+/* required. */
+
+/* B (input) REAL array, dimension (LDB,NRHS) */
+/* The right hand side matrix B. */
+
+/* LDB (input) INTEGER */
+/* The leading dimension of the array B. LDB >= max(1,N). */
+
+/* X (input/output) REAL array, dimension (LDX,NRHS) */
+/* On entry, the solution matrix X, as computed by SGTTRS. */
+/* On exit, the improved solution matrix X. */
+
+/* LDX (input) INTEGER */
+/* The leading dimension of the array X. LDX >= max(1,N). */
+
+/* FERR (output) REAL array, dimension (NRHS) */
+/* The estimated forward error bound for each solution vector */
+/* X(j) (the j-th column of the solution matrix X). */
+/* If XTRUE is the true solution corresponding to X(j), FERR(j) */
+/* is an estimated upper bound for the magnitude of the largest */
+/* element in (X(j) - XTRUE) divided by the magnitude of the */
+/* largest element in X(j). The estimate is as reliable as */
+/* the estimate for RCOND, and is almost always a slight */
+/* overestimate of the true error. */
+
+/* BERR (output) REAL array, dimension (NRHS) */
+/* The componentwise relative backward error of each solution */
+/* vector X(j) (i.e., the smallest relative change in */
+/* any element of A or B that makes X(j) an exact solution). */
+
+/* WORK (workspace) REAL array, dimension (3*N) */
+
+/* IWORK (workspace) INTEGER array, dimension (N) */
+
+/* INFO (output) INTEGER */
+/* = 0: successful exit */
+/* < 0: if INFO = -i, the i-th argument had an illegal value */
+
+/* Internal Parameters */
+/* =================== */
+
+/* ITMAX is the maximum number of steps of iterative refinement. */
+
+/* ===================================================================== */
+
+/* .. Parameters .. */
+/* .. */
+/* .. Local Scalars .. */
+/* .. */
+/* .. Local Arrays .. */
+/* .. */
+/* .. External Subroutines .. */
+/* .. */
+/* .. Intrinsic Functions .. */
+/* .. */
+/* .. External Functions .. */
+/* .. */
+/* .. Executable Statements .. */
+
+/* Test the input parameters. */
+
+ /* Parameter adjustments */
+ --dl;
+ --d__;
+ --du;
+ --dlf;
+ --df;
+ --duf;
+ --du2;
+ --ipiv;
+ b_dim1 = *ldb;
+ b_offset = 1 + b_dim1;
+ b -= b_offset;
+ x_dim1 = *ldx;
+ x_offset = 1 + x_dim1;
+ x -= x_offset;
+ --ferr;
+ --berr;
+ --work;
+ --iwork;
+
+ /* Function Body */
+ *info = 0;
+ notran = lsame_(trans, "N");
+ if (! notran && ! lsame_(trans, "T") && ! lsame_(
+ trans, "C")) {
+ *info = -1;
+ } else if (*n < 0) {
+ *info = -2;
+ } else if (*nrhs < 0) {
+ *info = -3;
+ } else if (*ldb < max(1,*n)) {
+ *info = -13;
+ } else if (*ldx < max(1,*n)) {
+ *info = -15;
+ }
+ if (*info != 0) {
+ i__1 = -(*info);
+ xerbla_("SGTRFS", &i__1);
+ return 0;
+ }
+
+/* Quick return if possible */
+
+ if (*n == 0 || *nrhs == 0) {
+ i__1 = *nrhs;
+ for (j = 1; j <= i__1; ++j) {
+ ferr[j] = 0.f;
+ berr[j] = 0.f;
+/* L10: */
+ }
+ return 0;
+ }
+
+ if (notran) {
+ *(unsigned char *)transn = 'N';
+ *(unsigned char *)transt = 'T';
+ } else {
+ *(unsigned char *)transn = 'T';
+ *(unsigned char *)transt = 'N';
+ }
+
+/* NZ = maximum number of nonzero elements in each row of A, plus 1 */
+
+ nz = 4;
+ eps = slamch_("Epsilon");
+ safmin = slamch_("Safe minimum");
+ safe1 = nz * safmin;
+ safe2 = safe1 / eps;
+
+/* Do for each right hand side */
+
+ i__1 = *nrhs;
+ for (j = 1; j <= i__1; ++j) {
+
+ count = 1;
+ lstres = 3.f;
+L20:
+
+/* Loop until stopping criterion is satisfied. */
+
+/* Compute residual R = B - op(A) * X, */
+/* where op(A) = A, A**T, or A**H, depending on TRANS. */
+
+ scopy_(n, &b[j * b_dim1 + 1], &c__1, &work[*n + 1], &c__1);
+ slagtm_(trans, n, &c__1, &c_b18, &dl[1], &d__[1], &du[1], &x[j *
+ x_dim1 + 1], ldx, &c_b19, &work[*n + 1], n);
+
+/* Compute abs(op(A))*abs(x) + abs(b) for use in the backward */
+/* error bound. */
+
+ if (notran) {
+ if (*n == 1) {
+ work[1] = (r__1 = b[j * b_dim1 + 1], dabs(r__1)) + (r__2 =
+ d__[1] * x[j * x_dim1 + 1], dabs(r__2));
+ } else {
+ work[1] = (r__1 = b[j * b_dim1 + 1], dabs(r__1)) + (r__2 =
+ d__[1] * x[j * x_dim1 + 1], dabs(r__2)) + (r__3 = du[
+ 1] * x[j * x_dim1 + 2], dabs(r__3));
+ i__2 = *n - 1;
+ for (i__ = 2; i__ <= i__2; ++i__) {
+ work[i__] = (r__1 = b[i__ + j * b_dim1], dabs(r__1)) + (
+ r__2 = dl[i__ - 1] * x[i__ - 1 + j * x_dim1],
+ dabs(r__2)) + (r__3 = d__[i__] * x[i__ + j *
+ x_dim1], dabs(r__3)) + (r__4 = du[i__] * x[i__ +
+ 1 + j * x_dim1], dabs(r__4));
+/* L30: */
+ }
+ work[*n] = (r__1 = b[*n + j * b_dim1], dabs(r__1)) + (r__2 =
+ dl[*n - 1] * x[*n - 1 + j * x_dim1], dabs(r__2)) + (
+ r__3 = d__[*n] * x[*n + j * x_dim1], dabs(r__3));
+ }
+ } else {
+ if (*n == 1) {
+ work[1] = (r__1 = b[j * b_dim1 + 1], dabs(r__1)) + (r__2 =
+ d__[1] * x[j * x_dim1 + 1], dabs(r__2));
+ } else {
+ work[1] = (r__1 = b[j * b_dim1 + 1], dabs(r__1)) + (r__2 =
+ d__[1] * x[j * x_dim1 + 1], dabs(r__2)) + (r__3 = dl[
+ 1] * x[j * x_dim1 + 2], dabs(r__3));
+ i__2 = *n - 1;
+ for (i__ = 2; i__ <= i__2; ++i__) {
+ work[i__] = (r__1 = b[i__ + j * b_dim1], dabs(r__1)) + (
+ r__2 = du[i__ - 1] * x[i__ - 1 + j * x_dim1],
+ dabs(r__2)) + (r__3 = d__[i__] * x[i__ + j *
+ x_dim1], dabs(r__3)) + (r__4 = dl[i__] * x[i__ +
+ 1 + j * x_dim1], dabs(r__4));
+/* L40: */
+ }
+ work[*n] = (r__1 = b[*n + j * b_dim1], dabs(r__1)) + (r__2 =
+ du[*n - 1] * x[*n - 1 + j * x_dim1], dabs(r__2)) + (
+ r__3 = d__[*n] * x[*n + j * x_dim1], dabs(r__3));
+ }
+ }
+
+/* Compute componentwise relative backward error from formula */
+
+/* max(i) ( abs(R(i)) / ( abs(op(A))*abs(X) + abs(B) )(i) ) */
+
+/* where abs(Z) is the componentwise absolute value of the matrix */
+/* or vector Z. If the i-th component of the denominator is less */
+/* than SAFE2, then SAFE1 is added to the i-th components of the */
+/* numerator and denominator before dividing. */
+
+ s = 0.f;
+ i__2 = *n;
+ for (i__ = 1; i__ <= i__2; ++i__) {
+ if (work[i__] > safe2) {
+/* Computing MAX */
+ r__2 = s, r__3 = (r__1 = work[*n + i__], dabs(r__1)) / work[
+ i__];
+ s = dmax(r__2,r__3);
+ } else {
+/* Computing MAX */
+ r__2 = s, r__3 = ((r__1 = work[*n + i__], dabs(r__1)) + safe1)
+ / (work[i__] + safe1);
+ s = dmax(r__2,r__3);
+ }
+/* L50: */
+ }
+ berr[j] = s;
+
+/* Test stopping criterion. Continue iterating if */
+/* 1) The residual BERR(J) is larger than machine epsilon, and */
+/* 2) BERR(J) decreased by at least a factor of 2 during the */
+/* last iteration, and */
+/* 3) At most ITMAX iterations tried. */
+
+ if (berr[j] > eps && berr[j] * 2.f <= lstres && count <= 5) {
+
+/* Update solution and try again. */
+
+ sgttrs_(trans, n, &c__1, &dlf[1], &df[1], &duf[1], &du2[1], &ipiv[
+ 1], &work[*n + 1], n, info);
+ saxpy_(n, &c_b19, &work[*n + 1], &c__1, &x[j * x_dim1 + 1], &c__1)
+ ;
+ lstres = berr[j];
+ ++count;
+ goto L20;
+ }
+
+/* Bound error from formula */
+
+/* norm(X - XTRUE) / norm(X) .le. FERR = */
+/* norm( abs(inv(op(A)))* */
+/* ( abs(R) + NZ*EPS*( abs(op(A))*abs(X)+abs(B) ))) / norm(X) */
+
+/* where */
+/* norm(Z) is the magnitude of the largest component of Z */
+/* inv(op(A)) is the inverse of op(A) */
+/* abs(Z) is the componentwise absolute value of the matrix or */
+/* vector Z */
+/* NZ is the maximum number of nonzeros in any row of A, plus 1 */
+/* EPS is machine epsilon */
+
+/* The i-th component of abs(R)+NZ*EPS*(abs(op(A))*abs(X)+abs(B)) */
+/* is incremented by SAFE1 if the i-th component of */
+/* abs(op(A))*abs(X) + abs(B) is less than SAFE2. */
+
+/* Use SLACN2 to estimate the infinity-norm of the matrix */
+/* inv(op(A)) * diag(W), */
+/* where W = abs(R) + NZ*EPS*( abs(op(A))*abs(X)+abs(B) ))) */
+
+ i__2 = *n;
+ for (i__ = 1; i__ <= i__2; ++i__) {
+ if (work[i__] > safe2) {
+ work[i__] = (r__1 = work[*n + i__], dabs(r__1)) + nz * eps *
+ work[i__];
+ } else {
+ work[i__] = (r__1 = work[*n + i__], dabs(r__1)) + nz * eps *
+ work[i__] + safe1;
+ }
+/* L60: */
+ }
+
+ kase = 0;
+L70:
+ slacn2_(n, &work[(*n << 1) + 1], &work[*n + 1], &iwork[1], &ferr[j], &
+ kase, isave);
+ if (kase != 0) {
+ if (kase == 1) {
+
+/* Multiply by diag(W)*inv(op(A)**T). */
+
+ sgttrs_(transt, n, &c__1, &dlf[1], &df[1], &duf[1], &du2[1], &
+ ipiv[1], &work[*n + 1], n, info);
+ i__2 = *n;
+ for (i__ = 1; i__ <= i__2; ++i__) {
+ work[*n + i__] = work[i__] * work[*n + i__];
+/* L80: */
+ }
+ } else {
+
+/* Multiply by inv(op(A))*diag(W). */
+
+ i__2 = *n;
+ for (i__ = 1; i__ <= i__2; ++i__) {
+ work[*n + i__] = work[i__] * work[*n + i__];
+/* L90: */
+ }
+ sgttrs_(transn, n, &c__1, &dlf[1], &df[1], &duf[1], &du2[1], &
+ ipiv[1], &work[*n + 1], n, info);
+ }
+ goto L70;
+ }
+
+/* Normalize error. */
+
+ lstres = 0.f;
+ i__2 = *n;
+ for (i__ = 1; i__ <= i__2; ++i__) {
+/* Computing MAX */
+ r__2 = lstres, r__3 = (r__1 = x[i__ + j * x_dim1], dabs(r__1));
+ lstres = dmax(r__2,r__3);
+/* L100: */
+ }
+ if (lstres != 0.f) {
+ ferr[j] /= lstres;
+ }
+
+/* L110: */
+ }
+
+ return 0;
+
+/* End of SGTRFS */
+
+} /* sgtrfs_ */