411 REFERENCE · Wikibooks
Linear Algebra and the C Language/a02c
Reference material by Wikibooks contributors. This retains its source identity and is not 411 news reporting.
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/* Save as : vgpivaid.h */
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double pivotbestAId_mR(
double **AId,
int pv
)
{
double pivotbest = fabs(AId[pv][pv]);
int best_r = pv;
int best_c = pv;
int r;
int c;
for ( r=pv; r<AId[R_SIZE][C0]; r++)
for ( c=pv; c<AId[R_SIZE][C0]; c++)
if(fabs(AId[r][c])>pivotbest)
{
pivotbest = fabs(AId[r][c]);
best_r = r;
best_c = c;
}
c--;
if(best_r!=pv) swapR_mR (AId,pv, best_r );
if(best_c!=pv) { swapC_withR0_mR(AId,pv, best_c );
swapC_withR0_mR(AId,pv+c,best_c+c);}
return(pivotbest);
}
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