32 lines
719 B
C++
32 lines
719 B
C++
#include "nr.h"
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void NR::wtn(Vec_IO_DP &a, Vec_I_INT &nn, const int isign,
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void wtstep(Vec_IO_DP &, const int, const int))
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{
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int idim,i1,i2,i3,k,n,nnew,nprev=1,nt,ntot=1;
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int ndim=nn.size();
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for (idim=0;idim<ndim;idim++) ntot *= nn[idim];
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for (idim=0;idim<ndim;idim++) {
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n=nn[idim];
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Vec_DP wksp(n);
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nnew=n*nprev;
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if (n > 4) {
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for (i2=0;i2<ntot;i2+=nnew) {
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for (i1=0;i1<nprev;i1++) {
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for (i3=i1+i2,k=0;k<n;k++,i3+=nprev) wksp[k]=a[i3];
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if (isign >= 0) {
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for(nt=n;nt>=4;nt >>= 1)
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wtstep(wksp,nt,isign);
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} else {
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for(nt=4;nt<=n;nt <<= 1)
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wtstep(wksp,nt,isign);
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}
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for (i3=i1+i2,k=0;k<n;k++,i3+=nprev) a[i3]=wksp[k];
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}
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}
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}
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nprev=nnew;
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}
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}
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