mirror of
https://github.com/opencv/opencv.git
synced 2024-12-02 16:00:17 +08:00
239 lines
6.2 KiB
C
239 lines
6.2 KiB
C
/* dsyr.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 "clapack.h"
|
|
|
|
|
|
/* Subroutine */ int dsyr_(char *uplo, integer *n, doublereal *alpha,
|
|
doublereal *x, integer *incx, doublereal *a, integer *lda)
|
|
{
|
|
/* System generated locals */
|
|
integer a_dim1, a_offset, i__1, i__2;
|
|
|
|
/* Local variables */
|
|
integer i__, j, ix, jx, kx, info;
|
|
doublereal temp;
|
|
extern logical lsame_(char *, char *);
|
|
extern /* Subroutine */ int xerbla_(char *, integer *);
|
|
|
|
/* .. Scalar Arguments .. */
|
|
/* .. */
|
|
/* .. Array Arguments .. */
|
|
/* .. */
|
|
|
|
/* Purpose */
|
|
/* ======= */
|
|
|
|
/* DSYR performs the symmetric rank 1 operation */
|
|
|
|
/* A := alpha*x*x' + A, */
|
|
|
|
/* where alpha is a real scalar, x is an n element vector and A is an */
|
|
/* n by n symmetric matrix. */
|
|
|
|
/* Arguments */
|
|
/* ========== */
|
|
|
|
/* UPLO - CHARACTER*1. */
|
|
/* On entry, UPLO specifies whether the upper or lower */
|
|
/* triangular part of the array A is to be referenced as */
|
|
/* follows: */
|
|
|
|
/* UPLO = 'U' or 'u' Only the upper triangular part of A */
|
|
/* is to be referenced. */
|
|
|
|
/* UPLO = 'L' or 'l' Only the lower triangular part of A */
|
|
/* is to be referenced. */
|
|
|
|
/* Unchanged on exit. */
|
|
|
|
/* N - INTEGER. */
|
|
/* On entry, N specifies the order of the matrix A. */
|
|
/* N must be at least zero. */
|
|
/* Unchanged on exit. */
|
|
|
|
/* ALPHA - DOUBLE PRECISION. */
|
|
/* On entry, ALPHA specifies the scalar alpha. */
|
|
/* Unchanged on exit. */
|
|
|
|
/* X - DOUBLE PRECISION array of dimension at least */
|
|
/* ( 1 + ( n - 1 )*abs( INCX ) ). */
|
|
/* Before entry, the incremented array X must contain the n */
|
|
/* element vector x. */
|
|
/* Unchanged on exit. */
|
|
|
|
/* INCX - INTEGER. */
|
|
/* On entry, INCX specifies the increment for the elements of */
|
|
/* X. INCX must not be zero. */
|
|
/* Unchanged on exit. */
|
|
|
|
/* A - DOUBLE PRECISION array of DIMENSION ( LDA, n ). */
|
|
/* Before entry with UPLO = 'U' or 'u', the leading n by n */
|
|
/* upper triangular part of the array A must contain the upper */
|
|
/* triangular part of the symmetric matrix and the strictly */
|
|
/* lower triangular part of A is not referenced. On exit, the */
|
|
/* upper triangular part of the array A is overwritten by the */
|
|
/* upper triangular part of the updated matrix. */
|
|
/* Before entry with UPLO = 'L' or 'l', the leading n by n */
|
|
/* lower triangular part of the array A must contain the lower */
|
|
/* triangular part of the symmetric matrix and the strictly */
|
|
/* upper triangular part of A is not referenced. On exit, the */
|
|
/* lower triangular part of the array A is overwritten by the */
|
|
/* lower triangular part of the updated matrix. */
|
|
|
|
/* LDA - INTEGER. */
|
|
/* On entry, LDA specifies the first dimension of A as declared */
|
|
/* in the calling (sub) program. LDA must be at least */
|
|
/* max( 1, n ). */
|
|
/* Unchanged on exit. */
|
|
|
|
|
|
/* Level 2 Blas routine. */
|
|
|
|
/* -- Written on 22-October-1986. */
|
|
/* Jack Dongarra, Argonne National Lab. */
|
|
/* Jeremy Du Croz, Nag Central Office. */
|
|
/* Sven Hammarling, Nag Central Office. */
|
|
/* Richard Hanson, Sandia National Labs. */
|
|
|
|
|
|
/* .. Parameters .. */
|
|
/* .. */
|
|
/* .. Local Scalars .. */
|
|
/* .. */
|
|
/* .. External Functions .. */
|
|
/* .. */
|
|
/* .. External Subroutines .. */
|
|
/* .. */
|
|
/* .. Intrinsic Functions .. */
|
|
/* .. */
|
|
|
|
/* Test the input parameters. */
|
|
|
|
/* Parameter adjustments */
|
|
--x;
|
|
a_dim1 = *lda;
|
|
a_offset = 1 + a_dim1;
|
|
a -= a_offset;
|
|
|
|
/* Function Body */
|
|
info = 0;
|
|
if (! lsame_(uplo, "U") && ! lsame_(uplo, "L")) {
|
|
info = 1;
|
|
} else if (*n < 0) {
|
|
info = 2;
|
|
} else if (*incx == 0) {
|
|
info = 5;
|
|
} else if (*lda < max(1,*n)) {
|
|
info = 7;
|
|
}
|
|
if (info != 0) {
|
|
xerbla_("DSYR ", &info);
|
|
return 0;
|
|
}
|
|
|
|
/* Quick return if possible. */
|
|
|
|
if (*n == 0 || *alpha == 0.) {
|
|
return 0;
|
|
}
|
|
|
|
/* Set the start point in X if the increment is not unity. */
|
|
|
|
if (*incx <= 0) {
|
|
kx = 1 - (*n - 1) * *incx;
|
|
} else if (*incx != 1) {
|
|
kx = 1;
|
|
}
|
|
|
|
/* Start the operations. In this version the elements of A are */
|
|
/* accessed sequentially with one pass through the triangular part */
|
|
/* of A. */
|
|
|
|
if (lsame_(uplo, "U")) {
|
|
|
|
/* Form A when A is stored in upper triangle. */
|
|
|
|
if (*incx == 1) {
|
|
i__1 = *n;
|
|
for (j = 1; j <= i__1; ++j) {
|
|
if (x[j] != 0.) {
|
|
temp = *alpha * x[j];
|
|
i__2 = j;
|
|
for (i__ = 1; i__ <= i__2; ++i__) {
|
|
a[i__ + j * a_dim1] += x[i__] * temp;
|
|
/* L10: */
|
|
}
|
|
}
|
|
/* L20: */
|
|
}
|
|
} else {
|
|
jx = kx;
|
|
i__1 = *n;
|
|
for (j = 1; j <= i__1; ++j) {
|
|
if (x[jx] != 0.) {
|
|
temp = *alpha * x[jx];
|
|
ix = kx;
|
|
i__2 = j;
|
|
for (i__ = 1; i__ <= i__2; ++i__) {
|
|
a[i__ + j * a_dim1] += x[ix] * temp;
|
|
ix += *incx;
|
|
/* L30: */
|
|
}
|
|
}
|
|
jx += *incx;
|
|
/* L40: */
|
|
}
|
|
}
|
|
} else {
|
|
|
|
/* Form A when A is stored in lower triangle. */
|
|
|
|
if (*incx == 1) {
|
|
i__1 = *n;
|
|
for (j = 1; j <= i__1; ++j) {
|
|
if (x[j] != 0.) {
|
|
temp = *alpha * x[j];
|
|
i__2 = *n;
|
|
for (i__ = j; i__ <= i__2; ++i__) {
|
|
a[i__ + j * a_dim1] += x[i__] * temp;
|
|
/* L50: */
|
|
}
|
|
}
|
|
/* L60: */
|
|
}
|
|
} else {
|
|
jx = kx;
|
|
i__1 = *n;
|
|
for (j = 1; j <= i__1; ++j) {
|
|
if (x[jx] != 0.) {
|
|
temp = *alpha * x[jx];
|
|
ix = jx;
|
|
i__2 = *n;
|
|
for (i__ = j; i__ <= i__2; ++i__) {
|
|
a[i__ + j * a_dim1] += x[ix] * temp;
|
|
ix += *incx;
|
|
/* L70: */
|
|
}
|
|
}
|
|
jx += *incx;
|
|
/* L80: */
|
|
}
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
|
|
/* End of DSYR . */
|
|
|
|
} /* dsyr_ */
|