mirror of https://github.com/opencv/opencv.git
Open Source Computer Vision Library
https://opencv.org/
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
313 lines
7.9 KiB
313 lines
7.9 KiB
/* ssymv.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 ssymv_(char *uplo, integer *n, real *alpha, real *a, |
|
integer *lda, real *x, integer *incx, real *beta, real *y, integer * |
|
incy) |
|
{ |
|
/* System generated locals */ |
|
integer a_dim1, a_offset, i__1, i__2; |
|
|
|
/* Local variables */ |
|
integer i__, j, ix, iy, jx, jy, kx, ky, info; |
|
real temp1, temp2; |
|
extern logical lsame_(char *, char *); |
|
extern /* Subroutine */ int xerbla_(char *, integer *); |
|
|
|
/* .. Scalar Arguments .. */ |
|
/* .. */ |
|
/* .. Array Arguments .. */ |
|
/* .. */ |
|
|
|
/* Purpose */ |
|
/* ======= */ |
|
|
|
/* SSYMV performs the matrix-vector operation */ |
|
|
|
/* y := alpha*A*x + beta*y, */ |
|
|
|
/* where alpha and beta are scalars, x and y are n element vectors 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 - REAL . */ |
|
/* On entry, ALPHA specifies the scalar alpha. */ |
|
/* Unchanged on exit. */ |
|
|
|
/* A - REAL 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. */ |
|
/* 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. */ |
|
/* Unchanged on exit. */ |
|
|
|
/* 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. */ |
|
|
|
/* X - REAL 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. */ |
|
|
|
/* BETA - REAL . */ |
|
/* On entry, BETA specifies the scalar beta. When BETA is */ |
|
/* supplied as zero then Y need not be set on input. */ |
|
/* Unchanged on exit. */ |
|
|
|
/* Y - REAL array of dimension at least */ |
|
/* ( 1 + ( n - 1 )*abs( INCY ) ). */ |
|
/* Before entry, the incremented array Y must contain the n */ |
|
/* element vector y. On exit, Y is overwritten by the updated */ |
|
/* vector y. */ |
|
|
|
/* INCY - INTEGER. */ |
|
/* On entry, INCY specifies the increment for the elements of */ |
|
/* Y. INCY must not be zero. */ |
|
/* 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 */ |
|
a_dim1 = *lda; |
|
a_offset = 1 + a_dim1; |
|
a -= a_offset; |
|
--x; |
|
--y; |
|
|
|
/* Function Body */ |
|
info = 0; |
|
if (! lsame_(uplo, "U") && ! lsame_(uplo, "L")) { |
|
info = 1; |
|
} else if (*n < 0) { |
|
info = 2; |
|
} else if (*lda < max(1,*n)) { |
|
info = 5; |
|
} else if (*incx == 0) { |
|
info = 7; |
|
} else if (*incy == 0) { |
|
info = 10; |
|
} |
|
if (info != 0) { |
|
xerbla_("SSYMV ", &info); |
|
return 0; |
|
} |
|
|
|
/* Quick return if possible. */ |
|
|
|
if (*n == 0 || *alpha == 0.f && *beta == 1.f) { |
|
return 0; |
|
} |
|
|
|
/* Set up the start points in X and Y. */ |
|
|
|
if (*incx > 0) { |
|
kx = 1; |
|
} else { |
|
kx = 1 - (*n - 1) * *incx; |
|
} |
|
if (*incy > 0) { |
|
ky = 1; |
|
} else { |
|
ky = 1 - (*n - 1) * *incy; |
|
} |
|
|
|
/* Start the operations. In this version the elements of A are */ |
|
/* accessed sequentially with one pass through the triangular part */ |
|
/* of A. */ |
|
|
|
/* First form y := beta*y. */ |
|
|
|
if (*beta != 1.f) { |
|
if (*incy == 1) { |
|
if (*beta == 0.f) { |
|
i__1 = *n; |
|
for (i__ = 1; i__ <= i__1; ++i__) { |
|
y[i__] = 0.f; |
|
/* L10: */ |
|
} |
|
} else { |
|
i__1 = *n; |
|
for (i__ = 1; i__ <= i__1; ++i__) { |
|
y[i__] = *beta * y[i__]; |
|
/* L20: */ |
|
} |
|
} |
|
} else { |
|
iy = ky; |
|
if (*beta == 0.f) { |
|
i__1 = *n; |
|
for (i__ = 1; i__ <= i__1; ++i__) { |
|
y[iy] = 0.f; |
|
iy += *incy; |
|
/* L30: */ |
|
} |
|
} else { |
|
i__1 = *n; |
|
for (i__ = 1; i__ <= i__1; ++i__) { |
|
y[iy] = *beta * y[iy]; |
|
iy += *incy; |
|
/* L40: */ |
|
} |
|
} |
|
} |
|
} |
|
if (*alpha == 0.f) { |
|
return 0; |
|
} |
|
if (lsame_(uplo, "U")) { |
|
|
|
/* Form y when A is stored in upper triangle. */ |
|
|
|
if (*incx == 1 && *incy == 1) { |
|
i__1 = *n; |
|
for (j = 1; j <= i__1; ++j) { |
|
temp1 = *alpha * x[j]; |
|
temp2 = 0.f; |
|
i__2 = j - 1; |
|
for (i__ = 1; i__ <= i__2; ++i__) { |
|
y[i__] += temp1 * a[i__ + j * a_dim1]; |
|
temp2 += a[i__ + j * a_dim1] * x[i__]; |
|
/* L50: */ |
|
} |
|
y[j] = y[j] + temp1 * a[j + j * a_dim1] + *alpha * temp2; |
|
/* L60: */ |
|
} |
|
} else { |
|
jx = kx; |
|
jy = ky; |
|
i__1 = *n; |
|
for (j = 1; j <= i__1; ++j) { |
|
temp1 = *alpha * x[jx]; |
|
temp2 = 0.f; |
|
ix = kx; |
|
iy = ky; |
|
i__2 = j - 1; |
|
for (i__ = 1; i__ <= i__2; ++i__) { |
|
y[iy] += temp1 * a[i__ + j * a_dim1]; |
|
temp2 += a[i__ + j * a_dim1] * x[ix]; |
|
ix += *incx; |
|
iy += *incy; |
|
/* L70: */ |
|
} |
|
y[jy] = y[jy] + temp1 * a[j + j * a_dim1] + *alpha * temp2; |
|
jx += *incx; |
|
jy += *incy; |
|
/* L80: */ |
|
} |
|
} |
|
} else { |
|
|
|
/* Form y when A is stored in lower triangle. */ |
|
|
|
if (*incx == 1 && *incy == 1) { |
|
i__1 = *n; |
|
for (j = 1; j <= i__1; ++j) { |
|
temp1 = *alpha * x[j]; |
|
temp2 = 0.f; |
|
y[j] += temp1 * a[j + j * a_dim1]; |
|
i__2 = *n; |
|
for (i__ = j + 1; i__ <= i__2; ++i__) { |
|
y[i__] += temp1 * a[i__ + j * a_dim1]; |
|
temp2 += a[i__ + j * a_dim1] * x[i__]; |
|
/* L90: */ |
|
} |
|
y[j] += *alpha * temp2; |
|
/* L100: */ |
|
} |
|
} else { |
|
jx = kx; |
|
jy = ky; |
|
i__1 = *n; |
|
for (j = 1; j <= i__1; ++j) { |
|
temp1 = *alpha * x[jx]; |
|
temp2 = 0.f; |
|
y[jy] += temp1 * a[j + j * a_dim1]; |
|
ix = jx; |
|
iy = jy; |
|
i__2 = *n; |
|
for (i__ = j + 1; i__ <= i__2; ++i__) { |
|
ix += *incx; |
|
iy += *incy; |
|
y[iy] += temp1 * a[i__ + j * a_dim1]; |
|
temp2 += a[i__ + j * a_dim1] * x[ix]; |
|
/* L110: */ |
|
} |
|
y[jy] += *alpha * temp2; |
|
jx += *incx; |
|
jy += *incy; |
|
/* L120: */ |
|
} |
|
} |
|
} |
|
|
|
return 0; |
|
|
|
/* End of SSYMV . */ |
|
|
|
} /* ssymv_ */
|
|
|