38 lines
595 B
C
38 lines
595 B
C
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#include <math.h>
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#define SWAP(g,h) {y=(g);(g)=(h);(h)=y;}
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void elmhes(float **a, int n)
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{
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int m,j,i;
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float y,x;
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for (m=2;m<n;m++) {
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x=0.0;
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i=m;
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for (j=m;j<=n;j++) {
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if (fabs(a[j][m-1]) > fabs(x)) {
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x=a[j][m-1];
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i=j;
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}
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}
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if (i != m) {
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for (j=m-1;j<=n;j++) SWAP(a[i][j],a[m][j])
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for (j=1;j<=n;j++) SWAP(a[j][i],a[j][m])
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}
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if (x) {
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for (i=m+1;i<=n;i++) {
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if ((y=a[i][m-1]) != 0.0) {
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y /= x;
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a[i][m-1]=y;
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for (j=m;j<=n;j++)
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a[i][j] -= y*a[m][j];
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for (j=1;j<=n;j++)
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a[j][m] += y*a[j][i];
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}
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}
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}
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}
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}
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#undef SWAP
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