hypre/blas/dscal.c
2007-11-13 17:40:07 +00:00

109 lines
2.7 KiB
C

/*BHEADER**********************************************************************
* Copyright (c) 2007, Lawrence Livermore National Security, LLC.
* Produced at the Lawrence Livermore National Laboratory.
* Written by the HYPRE team. UCRL-CODE-222953.
* All rights reserved.
*
* This file is part of HYPRE (see http://www.llnl.gov/CASC/hypre/).
* Please see the COPYRIGHT_and_LICENSE file for the copyright notice,
* disclaimer, contact information and the GNU Lesser General Public License.
*
* HYPRE is free software; you can redistribute it and/or modify it under the
* terms of the GNU General Public License (as published by the Free Software
* Foundation) version 2.1 dated February 1999.
*
* HYPRE is distributed in the hope that it will be useful, but WITHOUT ANY
* WARRANTY; without even the IMPLIED WARRANTY OF MERCHANTABILITY or FITNESS
* FOR A PARTICULAR PURPOSE. See the terms and conditions of the GNU General
* Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program; if not, write to the Free Software Foundation,
* Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* $Revision$
***********************************************************************EHEADER*/
/* -- translated by f2c (version 19940927).
You must link the resulting object file with the libraries:
-lf2c -lm (in that order)
*/
#include "f2c.h"
#include "hypre_blas.h"
/* Subroutine */ int dscal_(integer *n, doublereal *da, doublereal *dx,
integer *incx)
{
/* System generated locals */
/* Local variables */
static integer i, m, nincx, mp1;
/* scales a vector by a constant.
uses unrolled loops for increment equal to one.
jack dongarra, linpack, 3/11/78.
modified 3/93 to return if incx .le. 0.
modified 12/3/93, array(1) declarations changed to array(*)
Parameter adjustments
Function Body */
#define DX(I) dx[(I)-1]
if (*n <= 0 || *incx <= 0) {
return 0;
}
if (*incx == 1) {
goto L20;
}
/* code for increment not equal to 1 */
nincx = *n * *incx;
for (i = 1; *incx < 0 ? i >= nincx : i <= nincx; i += *incx) {
DX(i) = *da * DX(i);
/* L10: */
}
return 0;
/* code for increment equal to 1
clean-up loop */
L20:
m = *n % 5;
if (m == 0) {
goto L40;
}
for (i = 1; i <= m; ++i) {
DX(i) = *da * DX(i);
/* L30: */
}
if (*n < 5) {
return 0;
}
L40:
mp1 = m + 1;
for (i = mp1; i <= *n; i += 5) {
DX(i) = *da * DX(i);
DX(i + 1) = *da * DX(i + 1);
DX(i + 2) = *da * DX(i + 2);
DX(i + 3) = *da * DX(i + 3);
DX(i + 4) = *da * DX(i + 4);
/* L50: */
}
return 0;
} /* dscal_ */