39 lines
605 B
C++
39 lines
605 B
C++
#include <cmath>
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#include "nr.h"
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using namespace std;
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void NR::polcof(Vec_I_DP &xa, Vec_I_DP &ya, Vec_O_DP &cof)
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{
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int k,j,i;
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DP xmin,dy;
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int n=xa.size();
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Vec_DP x(n),y(n);
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for (j=0;j<n;j++) {
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x[j]=xa[j];
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y[j]=ya[j];
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}
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for (j=0;j<n;j++) {
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Vec_DP x_t(n-j),y_t(n-j);
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for (k=0;k<n-j;k++) {
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x_t[k]=x[k];
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y_t[k]=y[k];
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}
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polint(x_t,y_t,0.0,cof[j],dy);
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xmin=1.0e38;
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k = -1;
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for (i=0;i<n-j;i++) {
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if (fabs(x[i]) < xmin) {
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xmin=fabs(x[i]);
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k=i;
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}
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if (x[i] != 0.0)
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y[i]=(y[i]-cof[j])/x[i];
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}
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for (i=k+1;i<n-j;i++) {
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y[i-1]=y[i];
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x[i-1]=x[i];
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}
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}
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}
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