atl_henrm.c

来自「基于Blas CLapck的.用过的人知道是干啥的」· C语言 代码 · 共 84 行

/*
 *             Automatically Tuned Linear Algebra Software v3.8.0
 *                   (C) Copyright 1999 Antoine P. Petitet
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *   1. Redistributions of source code must retain the above copyright
 *      notice, this list of conditions and the following disclaimer.
 *   2. Redistributions in binary form must reproduce the above copyright
 *      notice, this list of conditions, and the following disclaimer in the
 *      documentation and/or other materials provided with the distribution.
 *   3. The name of the ATLAS group or the names of its contributers may
 *      not be used to endorse or promote products derived from this
 *      software without specific written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE ATLAS GROUP OR ITS CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *
 */
#include "atlas_misc.h"
#include "atlas_tst.h"
#include "atlas_level1.h"

TYPE Mjoin(PATL,henrm)
(const enum ATLAS_UPLO UPLO, const int N, const TYPE *A, const int LDA)
{
   int                        i, iaij, j, jaj, lda2 = ( LDA SHIFT ),
                              ldap12 = ( ( LDA + 1 ) SHIFT );
   TYPE max=ATL_rzero, t0, * work= NULL;

   if( N <= 0 ) return( ATL_rzero );

   work = (TYPE *)malloc( N * sizeof( TYPE ) );
   if( work == NULL )
   {fprintf( stderr, "mem alloc failed in [sy,he]nrm, bye ...\n" ); exit( 1 );}
   else { for( i = 0; i < N; i++ ) work[i] = ATL_rzero; }

   if( UPLO == AtlasUpper )
   {
      for( j = 0, jaj = 0; j < N; j++, jaj += lda2 )
      {
         work[j] = t0 = ATL_rzero;

         for( i = 0, iaij = jaj; i < j; i++, iaij += (1 SHIFT) )
         {
            work[i] += Mabs( A[iaij] ) + Mabs( A[iaij+1] );
            t0      += Mabs( A[iaij] ) + Mabs( A[iaij+1] );
         }
         work[j] += Mabs( A[iaij] ) + t0;
      }
   }
   else
   {
      for( j = 0, jaj = 0; j < N; j++, jaj += ldap12 )
      {
         t0      = ATL_rzero;
         work[j] = Mabs( A[jaj] );
         for( i = j+1, iaij = jaj+(1 SHIFT); i < N; i++, iaij += (1 SHIFT) )
         {
            work[i] += Mabs( A[iaij] ) + Mabs( A[iaij+1] );
            t0      += Mabs( A[iaij] ) + Mabs( A[iaij+1] );
         }
         work[j] += t0;
      }
   }

   max = work[0];
   for( j = 1; j < N; j++ ) if( max < work[j] ) max = work[j];

   if( work ) free( work );

   return( max );
}