27 lines
525 B
C
27 lines
525 B
C
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#include <math.h>
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#include "nrutil.h"
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void qrupdt(r,qt,n,u,v)
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float **qt,**r,u[],v[];
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int n;
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{
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void rotate();
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int i,j,k;
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for (k=n;k>=1;k--) {
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if (u[k]) break;
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}
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if (k < 1) k=1;
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for (i=k-1;i>=1;i--) {
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rotate(r,qt,n,i,u[i],-u[i+1]);
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if (u[i] == 0.0) u[i]=fabs(u[i+1]);
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else if (fabs(u[i]) > fabs(u[i+1]))
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u[i]=fabs(u[i])*sqrt(1.0+SQR(u[i+1]/u[i]));
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else u[i]=fabs(u[i+1])*sqrt(1.0+SQR(u[i]/u[i+1]));
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}
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for (j=1;j<=n;j++) r[1][j] += u[1]*v[j];
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for (i=1;i<k;i++)
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rotate(r,qt,n,i,r[i][i],-r[i+1][i]);
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}
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