Blame lib/smallft.c

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/********************************************************************
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 *                                                                  *
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 * THIS FILE IS PART OF THE OggVorbis SOFTWARE CODEC SOURCE CODE.   *
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 * USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS     *
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 * GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE *
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 * IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING.       *
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 *                                                                  *
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 * THE OggVorbis SOURCE CODE IS (C) COPYRIGHT 1994-2009             *
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 * by the Xiph.Org Foundation http://www.xiph.org/                  *
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 *                                                                  *
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 ********************************************************************
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 function: *unnormalized* fft transform
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 last mod: $Id: smallft.c 16227 2009-07-08 06:58:46Z xiphmont $
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 ********************************************************************/
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/* FFT implementation from OggSquish, minus cosine transforms,
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 * minus all but radix 2/4 case.  In Vorbis we only need this
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 * cut-down version.
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 *
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 * To do more than just power-of-two sized vectors, see the full
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 * version I wrote for NetLib.
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 *
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 * Note that the packing is a little strange; rather than the FFT r/i
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 * packing following R_0, I_n, R_1, I_1, R_2, I_2 ... R_n-1, I_n-1,
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 * it follows R_0, R_1, I_1, R_2, I_2 ... R_n-1, I_n-1, I_n like the
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 * FORTRAN version
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 */
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#include <stdlib.h>
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#include <string.h>
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#include <math.h>
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#include "smallft.h"
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#include "os.h"
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#include "misc.h"
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static void drfti1(int n, float *wa, int *ifac){
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  static int ntryh[4] = { 4,2,3,5 };
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  static float tpi = 6.28318530717958648f;
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  float arg,argh,argld,fi;
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  int ntry=0,i,j=-1;
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  int k1, l1, l2, ib;
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  int ld, ii, ip, is, nq, nr;
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  int ido, ipm, nfm1;
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  int nl=n;
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  int nf=0;
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 L101:
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  j++;
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  if (j < 4)
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    ntry=ntryh[j];
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  else
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    ntry+=2;
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 L104:
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  nq=nl/ntry;
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  nr=nl-ntry*nq;
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  if (nr!=0) goto L101;
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  nf++;
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  ifac[nf+1]=ntry;
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  nl=nq;
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  if(ntry!=2)goto L107;
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  if(nf==1)goto L107;
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  for (i=1;i
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    ib=nf-i+1;
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    ifac[ib+1]=ifac[ib];
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  }
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  ifac[2] = 2;
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 L107:
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  if(nl!=1)goto L104;
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  ifac[0]=n;
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  ifac[1]=nf;
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  argh=tpi/n;
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  is=0;
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  nfm1=nf-1;
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  l1=1;
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  if(nfm1==0)return;
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  for (k1=0;k1
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    ip=ifac[k1+2];
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    ld=0;
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    l2=l1*ip;
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    ido=n/l2;
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    ipm=ip-1;
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    for (j=0;j
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      ld+=l1;
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      i=is;
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      argld=(float)ld*argh;
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      fi=0.f;
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      for (ii=2;ii
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        fi+=1.f;
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        arg=fi*argld;
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        wa[i++]=cos(arg);
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        wa[i++]=sin(arg);
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      }
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      is+=ido;
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    }
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    l1=l2;
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  }
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}
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static void fdrffti(int n, float *wsave, int *ifac){
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  if (n == 1) return;
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  drfti1(n, wsave+n, ifac);
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}
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static void dradf2(int ido,int l1,float *cc,float *ch,float *wa1){
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  int i,k;
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  float ti2,tr2;
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  int t0,t1,t2,t3,t4,t5,t6;
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  t1=0;
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  t0=(t2=l1*ido);
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  t3=ido<<1;
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  for(k=0;k
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    ch[t1<<1]=cc[t1]+cc[t2];
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    ch[(t1<<1)+t3-1]=cc[t1]-cc[t2];
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    t1+=ido;
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    t2+=ido;
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  }
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  if(ido<2)return;
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  if(ido==2)goto L105;
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  t1=0;
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  t2=t0;
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  for(k=0;k
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    t3=t2;
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    t4=(t1<<1)+(ido<<1);
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    t5=t1;
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    t6=t1+t1;
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    for(i=2;i
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      t3+=2;
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      t4-=2;
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      t5+=2;
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      t6+=2;
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      tr2=wa1[i-2]*cc[t3-1]+wa1[i-1]*cc[t3];
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      ti2=wa1[i-2]*cc[t3]-wa1[i-1]*cc[t3-1];
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      ch[t6]=cc[t5]+ti2;
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      ch[t4]=ti2-cc[t5];
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      ch[t6-1]=cc[t5-1]+tr2;
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      ch[t4-1]=cc[t5-1]-tr2;
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    }
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    t1+=ido;
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    t2+=ido;
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  }
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  if(ido%2==1)return;
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 L105:
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  t3=(t2=(t1=ido)-1);
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  t2+=t0;
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  for(k=0;k
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    ch[t1]=-cc[t2];
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    ch[t1-1]=cc[t3];
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    t1+=ido<<1;
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    t2+=ido;
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    t3+=ido;
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  }
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}
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static void dradf4(int ido,int l1,float *cc,float *ch,float *wa1,
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            float *wa2,float *wa3){
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  static float hsqt2 = .70710678118654752f;
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  int i,k,t0,t1,t2,t3,t4,t5,t6;
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  float ci2,ci3,ci4,cr2,cr3,cr4,ti1,ti2,ti3,ti4,tr1,tr2,tr3,tr4;
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  t0=l1*ido;
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  t1=t0;
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  t4=t1<<1;
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  t2=t1+(t1<<1);
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  t3=0;
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  for(k=0;k
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    tr1=cc[t1]+cc[t2];
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    tr2=cc[t3]+cc[t4];
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    ch[t5=t3<<2]=tr1+tr2;
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    ch[(ido<<2)+t5-1]=tr2-tr1;
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    ch[(t5+=(ido<<1))-1]=cc[t3]-cc[t4];
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    ch[t5]=cc[t2]-cc[t1];
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    t1+=ido;
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    t2+=ido;
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    t3+=ido;
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    t4+=ido;
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  }
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  if(ido<2)return;
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  if(ido==2)goto L105;
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  t1=0;
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  for(k=0;k
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    t2=t1;
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    t4=t1<<2;
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    t5=(t6=ido<<1)+t4;
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    for(i=2;i
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      t3=(t2+=2);
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      t4+=2;
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      t5-=2;
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      t3+=t0;
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      cr2=wa1[i-2]*cc[t3-1]+wa1[i-1]*cc[t3];
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      ci2=wa1[i-2]*cc[t3]-wa1[i-1]*cc[t3-1];
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      t3+=t0;
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      cr3=wa2[i-2]*cc[t3-1]+wa2[i-1]*cc[t3];
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      ci3=wa2[i-2]*cc[t3]-wa2[i-1]*cc[t3-1];
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      t3+=t0;
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      cr4=wa3[i-2]*cc[t3-1]+wa3[i-1]*cc[t3];
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      ci4=wa3[i-2]*cc[t3]-wa3[i-1]*cc[t3-1];
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      tr1=cr2+cr4;
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      tr4=cr4-cr2;
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      ti1=ci2+ci4;
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      ti4=ci2-ci4;
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      ti2=cc[t2]+ci3;
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      ti3=cc[t2]-ci3;
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      tr2=cc[t2-1]+cr3;
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      tr3=cc[t2-1]-cr3;
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      ch[t4-1]=tr1+tr2;
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      ch[t4]=ti1+ti2;
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      ch[t5-1]=tr3-ti4;
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      ch[t5]=tr4-ti3;
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      ch[t4+t6-1]=ti4+tr3;
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      ch[t4+t6]=tr4+ti3;
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      ch[t5+t6-1]=tr2-tr1;
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      ch[t5+t6]=ti1-ti2;
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    }
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    t1+=ido;
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  }
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  if(ido&1)return;
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 L105:
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  t2=(t1=t0+ido-1)+(t0<<1);
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  t3=ido<<2;
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  t4=ido;
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  t5=ido<<1;
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  t6=ido;
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  for(k=0;k
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    ti1=-hsqt2*(cc[t1]+cc[t2]);
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    tr1=hsqt2*(cc[t1]-cc[t2]);
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    ch[t4-1]=tr1+cc[t6-1];
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    ch[t4+t5-1]=cc[t6-1]-tr1;
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    ch[t4]=ti1-cc[t1+t0];
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    ch[t4+t5]=ti1+cc[t1+t0];
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    t1+=ido;
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    t2+=ido;
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    t4+=t3;
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    t6+=ido;
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  }
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}
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static void dradfg(int ido,int ip,int l1,int idl1,float *cc,float *c1,
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                          float *c2,float *ch,float *ch2,float *wa){
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  static float tpi=6.283185307179586f;
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  int idij,ipph,i,j,k,l,ic,ik,is;
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  int t0,t1,t2,t3,t4,t5,t6,t7,t8,t9,t10;
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  float dc2,ai1,ai2,ar1,ar2,ds2;
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  int nbd;
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  float dcp,arg,dsp,ar1h,ar2h;
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  int idp2,ipp2;
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  arg=tpi/(float)ip;
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  dcp=cos(arg);
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  dsp=sin(arg);
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  ipph=(ip+1)>>1;
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  ipp2=ip;
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  idp2=ido;
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  nbd=(ido-1)>>1;
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  t0=l1*ido;
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  t10=ip*ido;
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  if(ido==1)goto L119;
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  for(ik=0;ik
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  t1=0;
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  for(j=1;j
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    t1+=t0;
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    t2=t1;
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    for(k=0;k
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      ch[t2]=c1[t2];
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      t2+=ido;
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    }
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  }
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  is=-ido;
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  t1=0;
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  if(nbd>l1){
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    for(j=1;j
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      t1+=t0;
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      is+=ido;
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      t2= -ido+t1;
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      for(k=0;k
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        idij=is-1;
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        t2+=ido;
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        t3=t2;
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        for(i=2;i
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          idij+=2;
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          t3+=2;
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          ch[t3-1]=wa[idij-1]*c1[t3-1]+wa[idij]*c1[t3];
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          ch[t3]=wa[idij-1]*c1[t3]-wa[idij]*c1[t3-1];
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        }
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      }
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    }
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  }else{
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    for(j=1;j
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      is+=ido;
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      idij=is-1;
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      t1+=t0;
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      t2=t1;
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      for(i=2;i
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        idij+=2;
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        t2+=2;
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        t3=t2;
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        for(k=0;k
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          ch[t3-1]=wa[idij-1]*c1[t3-1]+wa[idij]*c1[t3];
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          ch[t3]=wa[idij-1]*c1[t3]-wa[idij]*c1[t3-1];
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          t3+=ido;
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        }
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      }
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    }
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  }
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  t1=0;
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  t2=ipp2*t0;
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  if(nbd
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    for(j=1;j
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      t1+=t0;
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      t2-=t0;
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      t3=t1;
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      t4=t2;
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      for(i=2;i
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        t3+=2;
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        t4+=2;
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        t5=t3-ido;
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        t6=t4-ido;
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        for(k=0;k
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          t5+=ido;
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          t6+=ido;
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          c1[t5-1]=ch[t5-1]+ch[t6-1];
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          c1[t6-1]=ch[t5]-ch[t6];
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          c1[t5]=ch[t5]+ch[t6];
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          c1[t6]=ch[t6-1]-ch[t5-1];
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        }
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      }
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    }
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  }else{
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    for(j=1;j
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      t1+=t0;
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      t2-=t0;
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      t3=t1;
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      t4=t2;
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      for(k=0;k
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        t5=t3;
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        t6=t4;
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        for(i=2;i
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          t5+=2;
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          t6+=2;
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          c1[t5-1]=ch[t5-1]+ch[t6-1];
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          c1[t6-1]=ch[t5]-ch[t6];
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          c1[t5]=ch[t5]+ch[t6];
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          c1[t6]=ch[t6-1]-ch[t5-1];
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        }
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        t3+=ido;
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        t4+=ido;
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      }
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    }
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  }
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L119:
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  for(ik=0;ik
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  t1=0;
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  t2=ipp2*idl1;
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  for(j=1;j
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    t1+=t0;
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    t2-=t0;
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    t3=t1-ido;
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    t4=t2-ido;
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    for(k=0;k
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      t3+=ido;
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      t4+=ido;
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      c1[t3]=ch[t3]+ch[t4];
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      c1[t4]=ch[t4]-ch[t3];
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    }
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  }
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  ar1=1.f;
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  ai1=0.f;
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  t1=0;
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  t2=ipp2*idl1;
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  t3=(ip-1)*idl1;
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  for(l=1;l
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    t1+=idl1;
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    t2-=idl1;
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    ar1h=dcp*ar1-dsp*ai1;
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    ai1=dcp*ai1+dsp*ar1;
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    ar1=ar1h;
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    t4=t1;
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    t5=t2;
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    t6=t3;
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    t7=idl1;
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    for(ik=0;ik
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      ch2[t4++]=c2[ik]+ar1*c2[t7++];
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      ch2[t5++]=ai1*c2[t6++];
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    }
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    dc2=ar1;
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    ds2=ai1;
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    ar2=ar1;
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    ai2=ai1;
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    t4=idl1;
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    t5=(ipp2-1)*idl1;
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    for(j=2;j
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      t4+=idl1;
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      t5-=idl1;
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      ar2h=dc2*ar2-ds2*ai2;
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      ai2=dc2*ai2+ds2*ar2;
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      ar2=ar2h;
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      t6=t1;
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      t7=t2;
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      t8=t4;
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      t9=t5;
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      for(ik=0;ik
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        ch2[t6++]+=ar2*c2[t8++];
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        ch2[t7++]+=ai2*c2[t9++];
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      }
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    }
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  }
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  t1=0;
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  for(j=1;j
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    t1+=idl1;
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    t2=t1;
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    for(ik=0;ik
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  }
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  if(ido
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  t1=0;
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  t2=0;
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  for(k=0;k
Packit 06404a
    t3=t1;
Packit 06404a
    t4=t2;
Packit 06404a
    for(i=0;i
Packit 06404a
    t1+=ido;
Packit 06404a
    t2+=t10;
Packit 06404a
  }
Packit 06404a
Packit 06404a
  goto L135;
Packit 06404a
Packit 06404a
 L132:
Packit 06404a
  for(i=0;i
Packit 06404a
    t1=i;
Packit 06404a
    t2=i;
Packit 06404a
    for(k=0;k
Packit 06404a
      cc[t2]=ch[t1];
Packit 06404a
      t1+=ido;
Packit 06404a
      t2+=t10;
Packit 06404a
    }
Packit 06404a
  }
Packit 06404a
Packit 06404a
 L135:
Packit 06404a
  t1=0;
Packit 06404a
  t2=ido<<1;
Packit 06404a
  t3=0;
Packit 06404a
  t4=ipp2*t0;
Packit 06404a
  for(j=1;j
Packit 06404a
Packit 06404a
    t1+=t2;
Packit 06404a
    t3+=t0;
Packit 06404a
    t4-=t0;
Packit 06404a
Packit 06404a
    t5=t1;
Packit 06404a
    t6=t3;
Packit 06404a
    t7=t4;
Packit 06404a
Packit 06404a
    for(k=0;k
Packit 06404a
      cc[t5-1]=ch[t6];
Packit 06404a
      cc[t5]=ch[t7];
Packit 06404a
      t5+=t10;
Packit 06404a
      t6+=ido;
Packit 06404a
      t7+=ido;
Packit 06404a
    }
Packit 06404a
  }
Packit 06404a
Packit 06404a
  if(ido==1)return;
Packit 06404a
  if(nbd
Packit 06404a
Packit 06404a
  t1=-ido;
Packit 06404a
  t3=0;
Packit 06404a
  t4=0;
Packit 06404a
  t5=ipp2*t0;
Packit 06404a
  for(j=1;j
Packit 06404a
    t1+=t2;
Packit 06404a
    t3+=t2;
Packit 06404a
    t4+=t0;
Packit 06404a
    t5-=t0;
Packit 06404a
    t6=t1;
Packit 06404a
    t7=t3;
Packit 06404a
    t8=t4;
Packit 06404a
    t9=t5;
Packit 06404a
    for(k=0;k
Packit 06404a
      for(i=2;i
Packit 06404a
        ic=idp2-i;
Packit 06404a
        cc[i+t7-1]=ch[i+t8-1]+ch[i+t9-1];
Packit 06404a
        cc[ic+t6-1]=ch[i+t8-1]-ch[i+t9-1];
Packit 06404a
        cc[i+t7]=ch[i+t8]+ch[i+t9];
Packit 06404a
        cc[ic+t6]=ch[i+t9]-ch[i+t8];
Packit 06404a
      }
Packit 06404a
      t6+=t10;
Packit 06404a
      t7+=t10;
Packit 06404a
      t8+=ido;
Packit 06404a
      t9+=ido;
Packit 06404a
    }
Packit 06404a
  }
Packit 06404a
  return;
Packit 06404a
Packit 06404a
 L141:
Packit 06404a
Packit 06404a
  t1=-ido;
Packit 06404a
  t3=0;
Packit 06404a
  t4=0;
Packit 06404a
  t5=ipp2*t0;
Packit 06404a
  for(j=1;j
Packit 06404a
    t1+=t2;
Packit 06404a
    t3+=t2;
Packit 06404a
    t4+=t0;
Packit 06404a
    t5-=t0;
Packit 06404a
    for(i=2;i
Packit 06404a
      t6=idp2+t1-i;
Packit 06404a
      t7=i+t3;
Packit 06404a
      t8=i+t4;
Packit 06404a
      t9=i+t5;
Packit 06404a
      for(k=0;k
Packit 06404a
        cc[t7-1]=ch[t8-1]+ch[t9-1];
Packit 06404a
        cc[t6-1]=ch[t8-1]-ch[t9-1];
Packit 06404a
        cc[t7]=ch[t8]+ch[t9];
Packit 06404a
        cc[t6]=ch[t9]-ch[t8];
Packit 06404a
        t6+=t10;
Packit 06404a
        t7+=t10;
Packit 06404a
        t8+=ido;
Packit 06404a
        t9+=ido;
Packit 06404a
      }
Packit 06404a
    }
Packit 06404a
  }
Packit 06404a
}
Packit 06404a
Packit 06404a
static void drftf1(int n,float *c,float *ch,float *wa,int *ifac){
Packit 06404a
  int i,k1,l1,l2;
Packit 06404a
  int na,kh,nf;
Packit 06404a
  int ip,iw,ido,idl1,ix2,ix3;
Packit 06404a
Packit 06404a
  nf=ifac[1];
Packit 06404a
  na=1;
Packit 06404a
  l2=n;
Packit 06404a
  iw=n;
Packit 06404a
Packit 06404a
  for(k1=0;k1
Packit 06404a
    kh=nf-k1;
Packit 06404a
    ip=ifac[kh+1];
Packit 06404a
    l1=l2/ip;
Packit 06404a
    ido=n/l2;
Packit 06404a
    idl1=ido*l1;
Packit 06404a
    iw-=(ip-1)*ido;
Packit 06404a
    na=1-na;
Packit 06404a
Packit 06404a
    if(ip!=4)goto L102;
Packit 06404a
Packit 06404a
    ix2=iw+ido;
Packit 06404a
    ix3=ix2+ido;
Packit 06404a
    if(na!=0)
Packit 06404a
      dradf4(ido,l1,ch,c,wa+iw-1,wa+ix2-1,wa+ix3-1);
Packit 06404a
    else
Packit 06404a
      dradf4(ido,l1,c,ch,wa+iw-1,wa+ix2-1,wa+ix3-1);
Packit 06404a
    goto L110;
Packit 06404a
Packit 06404a
 L102:
Packit 06404a
    if(ip!=2)goto L104;
Packit 06404a
    if(na!=0)goto L103;
Packit 06404a
Packit 06404a
    dradf2(ido,l1,c,ch,wa+iw-1);
Packit 06404a
    goto L110;
Packit 06404a
Packit 06404a
  L103:
Packit 06404a
    dradf2(ido,l1,ch,c,wa+iw-1);
Packit 06404a
    goto L110;
Packit 06404a
Packit 06404a
  L104:
Packit 06404a
    if(ido==1)na=1-na;
Packit 06404a
    if(na!=0)goto L109;
Packit 06404a
Packit 06404a
    dradfg(ido,ip,l1,idl1,c,c,c,ch,ch,wa+iw-1);
Packit 06404a
    na=1;
Packit 06404a
    goto L110;
Packit 06404a
Packit 06404a
  L109:
Packit 06404a
    dradfg(ido,ip,l1,idl1,ch,ch,ch,c,c,wa+iw-1);
Packit 06404a
    na=0;
Packit 06404a
Packit 06404a
  L110:
Packit 06404a
    l2=l1;
Packit 06404a
  }
Packit 06404a
Packit 06404a
  if(na==1)return;
Packit 06404a
Packit 06404a
  for(i=0;i
Packit 06404a
}
Packit 06404a
Packit 06404a
static void dradb2(int ido,int l1,float *cc,float *ch,float *wa1){
Packit 06404a
  int i,k,t0,t1,t2,t3,t4,t5,t6;
Packit 06404a
  float ti2,tr2;
Packit 06404a
Packit 06404a
  t0=l1*ido;
Packit 06404a
Packit 06404a
  t1=0;
Packit 06404a
  t2=0;
Packit 06404a
  t3=(ido<<1)-1;
Packit 06404a
  for(k=0;k
Packit 06404a
    ch[t1]=cc[t2]+cc[t3+t2];
Packit 06404a
    ch[t1+t0]=cc[t2]-cc[t3+t2];
Packit 06404a
    t2=(t1+=ido)<<1;
Packit 06404a
  }
Packit 06404a
Packit 06404a
  if(ido<2)return;
Packit 06404a
  if(ido==2)goto L105;
Packit 06404a
Packit 06404a
  t1=0;
Packit 06404a
  t2=0;
Packit 06404a
  for(k=0;k
Packit 06404a
    t3=t1;
Packit 06404a
    t5=(t4=t2)+(ido<<1);
Packit 06404a
    t6=t0+t1;
Packit 06404a
    for(i=2;i
Packit 06404a
      t3+=2;
Packit 06404a
      t4+=2;
Packit 06404a
      t5-=2;
Packit 06404a
      t6+=2;
Packit 06404a
      ch[t3-1]=cc[t4-1]+cc[t5-1];
Packit 06404a
      tr2=cc[t4-1]-cc[t5-1];
Packit 06404a
      ch[t3]=cc[t4]-cc[t5];
Packit 06404a
      ti2=cc[t4]+cc[t5];
Packit 06404a
      ch[t6-1]=wa1[i-2]*tr2-wa1[i-1]*ti2;
Packit 06404a
      ch[t6]=wa1[i-2]*ti2+wa1[i-1]*tr2;
Packit 06404a
    }
Packit 06404a
    t2=(t1+=ido)<<1;
Packit 06404a
  }
Packit 06404a
Packit 06404a
  if(ido%2==1)return;
Packit 06404a
Packit 06404a
L105:
Packit 06404a
  t1=ido-1;
Packit 06404a
  t2=ido-1;
Packit 06404a
  for(k=0;k
Packit 06404a
    ch[t1]=cc[t2]+cc[t2];
Packit 06404a
    ch[t1+t0]=-(cc[t2+1]+cc[t2+1]);
Packit 06404a
    t1+=ido;
Packit 06404a
    t2+=ido<<1;
Packit 06404a
  }
Packit 06404a
}
Packit 06404a
Packit 06404a
static void dradb3(int ido,int l1,float *cc,float *ch,float *wa1,
Packit 06404a
                          float *wa2){
Packit 06404a
  static float taur = -.5f;
Packit 06404a
  static float taui = .8660254037844386f;
Packit 06404a
  int i,k,t0,t1,t2,t3,t4,t5,t6,t7,t8,t9,t10;
Packit 06404a
  float ci2,ci3,di2,di3,cr2,cr3,dr2,dr3,ti2,tr2;
Packit 06404a
  t0=l1*ido;
Packit 06404a
Packit 06404a
  t1=0;
Packit 06404a
  t2=t0<<1;
Packit 06404a
  t3=ido<<1;
Packit 06404a
  t4=ido+(ido<<1);
Packit 06404a
  t5=0;
Packit 06404a
  for(k=0;k
Packit 06404a
    tr2=cc[t3-1]+cc[t3-1];
Packit 06404a
    cr2=cc[t5]+(taur*tr2);
Packit 06404a
    ch[t1]=cc[t5]+tr2;
Packit 06404a
    ci3=taui*(cc[t3]+cc[t3]);
Packit 06404a
    ch[t1+t0]=cr2-ci3;
Packit 06404a
    ch[t1+t2]=cr2+ci3;
Packit 06404a
    t1+=ido;
Packit 06404a
    t3+=t4;
Packit 06404a
    t5+=t4;
Packit 06404a
  }
Packit 06404a
Packit 06404a
  if(ido==1)return;
Packit 06404a
Packit 06404a
  t1=0;
Packit 06404a
  t3=ido<<1;
Packit 06404a
  for(k=0;k
Packit 06404a
    t7=t1+(t1<<1);
Packit 06404a
    t6=(t5=t7+t3);
Packit 06404a
    t8=t1;
Packit 06404a
    t10=(t9=t1+t0)+t0;
Packit 06404a
Packit 06404a
    for(i=2;i
Packit 06404a
      t5+=2;
Packit 06404a
      t6-=2;
Packit 06404a
      t7+=2;
Packit 06404a
      t8+=2;
Packit 06404a
      t9+=2;
Packit 06404a
      t10+=2;
Packit 06404a
      tr2=cc[t5-1]+cc[t6-1];
Packit 06404a
      cr2=cc[t7-1]+(taur*tr2);
Packit 06404a
      ch[t8-1]=cc[t7-1]+tr2;
Packit 06404a
      ti2=cc[t5]-cc[t6];
Packit 06404a
      ci2=cc[t7]+(taur*ti2);
Packit 06404a
      ch[t8]=cc[t7]+ti2;
Packit 06404a
      cr3=taui*(cc[t5-1]-cc[t6-1]);
Packit 06404a
      ci3=taui*(cc[t5]+cc[t6]);
Packit 06404a
      dr2=cr2-ci3;
Packit 06404a
      dr3=cr2+ci3;
Packit 06404a
      di2=ci2+cr3;
Packit 06404a
      di3=ci2-cr3;
Packit 06404a
      ch[t9-1]=wa1[i-2]*dr2-wa1[i-1]*di2;
Packit 06404a
      ch[t9]=wa1[i-2]*di2+wa1[i-1]*dr2;
Packit 06404a
      ch[t10-1]=wa2[i-2]*dr3-wa2[i-1]*di3;
Packit 06404a
      ch[t10]=wa2[i-2]*di3+wa2[i-1]*dr3;
Packit 06404a
    }
Packit 06404a
    t1+=ido;
Packit 06404a
  }
Packit 06404a
}
Packit 06404a
Packit 06404a
static void dradb4(int ido,int l1,float *cc,float *ch,float *wa1,
Packit 06404a
                          float *wa2,float *wa3){
Packit 06404a
  static float sqrt2=1.414213562373095f;
Packit 06404a
  int i,k,t0,t1,t2,t3,t4,t5,t6,t7,t8;
Packit 06404a
  float ci2,ci3,ci4,cr2,cr3,cr4,ti1,ti2,ti3,ti4,tr1,tr2,tr3,tr4;
Packit 06404a
  t0=l1*ido;
Packit 06404a
Packit 06404a
  t1=0;
Packit 06404a
  t2=ido<<2;
Packit 06404a
  t3=0;
Packit 06404a
  t6=ido<<1;
Packit 06404a
  for(k=0;k
Packit 06404a
    t4=t3+t6;
Packit 06404a
    t5=t1;
Packit 06404a
    tr3=cc[t4-1]+cc[t4-1];
Packit 06404a
    tr4=cc[t4]+cc[t4];
Packit 06404a
    tr1=cc[t3]-cc[(t4+=t6)-1];
Packit 06404a
    tr2=cc[t3]+cc[t4-1];
Packit 06404a
    ch[t5]=tr2+tr3;
Packit 06404a
    ch[t5+=t0]=tr1-tr4;
Packit 06404a
    ch[t5+=t0]=tr2-tr3;
Packit 06404a
    ch[t5+=t0]=tr1+tr4;
Packit 06404a
    t1+=ido;
Packit 06404a
    t3+=t2;
Packit 06404a
  }
Packit 06404a
Packit 06404a
  if(ido<2)return;
Packit 06404a
  if(ido==2)goto L105;
Packit 06404a
Packit 06404a
  t1=0;
Packit 06404a
  for(k=0;k
Packit 06404a
    t5=(t4=(t3=(t2=t1<<2)+t6))+t6;
Packit 06404a
    t7=t1;
Packit 06404a
    for(i=2;i
Packit 06404a
      t2+=2;
Packit 06404a
      t3+=2;
Packit 06404a
      t4-=2;
Packit 06404a
      t5-=2;
Packit 06404a
      t7+=2;
Packit 06404a
      ti1=cc[t2]+cc[t5];
Packit 06404a
      ti2=cc[t2]-cc[t5];
Packit 06404a
      ti3=cc[t3]-cc[t4];
Packit 06404a
      tr4=cc[t3]+cc[t4];
Packit 06404a
      tr1=cc[t2-1]-cc[t5-1];
Packit 06404a
      tr2=cc[t2-1]+cc[t5-1];
Packit 06404a
      ti4=cc[t3-1]-cc[t4-1];
Packit 06404a
      tr3=cc[t3-1]+cc[t4-1];
Packit 06404a
      ch[t7-1]=tr2+tr3;
Packit 06404a
      cr3=tr2-tr3;
Packit 06404a
      ch[t7]=ti2+ti3;
Packit 06404a
      ci3=ti2-ti3;
Packit 06404a
      cr2=tr1-tr4;
Packit 06404a
      cr4=tr1+tr4;
Packit 06404a
      ci2=ti1+ti4;
Packit 06404a
      ci4=ti1-ti4;
Packit 06404a
Packit 06404a
      ch[(t8=t7+t0)-1]=wa1[i-2]*cr2-wa1[i-1]*ci2;
Packit 06404a
      ch[t8]=wa1[i-2]*ci2+wa1[i-1]*cr2;
Packit 06404a
      ch[(t8+=t0)-1]=wa2[i-2]*cr3-wa2[i-1]*ci3;
Packit 06404a
      ch[t8]=wa2[i-2]*ci3+wa2[i-1]*cr3;
Packit 06404a
      ch[(t8+=t0)-1]=wa3[i-2]*cr4-wa3[i-1]*ci4;
Packit 06404a
      ch[t8]=wa3[i-2]*ci4+wa3[i-1]*cr4;
Packit 06404a
    }
Packit 06404a
    t1+=ido;
Packit 06404a
  }
Packit 06404a
Packit 06404a
  if(ido%2 == 1)return;
Packit 06404a
Packit 06404a
 L105:
Packit 06404a
Packit 06404a
  t1=ido;
Packit 06404a
  t2=ido<<2;
Packit 06404a
  t3=ido-1;
Packit 06404a
  t4=ido+(ido<<1);
Packit 06404a
  for(k=0;k
Packit 06404a
    t5=t3;
Packit 06404a
    ti1=cc[t1]+cc[t4];
Packit 06404a
    ti2=cc[t4]-cc[t1];
Packit 06404a
    tr1=cc[t1-1]-cc[t4-1];
Packit 06404a
    tr2=cc[t1-1]+cc[t4-1];
Packit 06404a
    ch[t5]=tr2+tr2;
Packit 06404a
    ch[t5+=t0]=sqrt2*(tr1-ti1);
Packit 06404a
    ch[t5+=t0]=ti2+ti2;
Packit 06404a
    ch[t5+=t0]=-sqrt2*(tr1+ti1);
Packit 06404a
Packit 06404a
    t3+=ido;
Packit 06404a
    t1+=t2;
Packit 06404a
    t4+=t2;
Packit 06404a
  }
Packit 06404a
}
Packit 06404a
Packit 06404a
static void dradbg(int ido,int ip,int l1,int idl1,float *cc,float *c1,
Packit 06404a
            float *c2,float *ch,float *ch2,float *wa){
Packit 06404a
  static float tpi=6.283185307179586f;
Packit 06404a
  int idij,ipph,i,j,k,l,ik,is,t0,t1,t2,t3,t4,t5,t6,t7,t8,t9,t10,
Packit 06404a
      t11,t12;
Packit 06404a
  float dc2,ai1,ai2,ar1,ar2,ds2;
Packit 06404a
  int nbd;
Packit 06404a
  float dcp,arg,dsp,ar1h,ar2h;
Packit 06404a
  int ipp2;
Packit 06404a
Packit 06404a
  t10=ip*ido;
Packit 06404a
  t0=l1*ido;
Packit 06404a
  arg=tpi/(float)ip;
Packit 06404a
  dcp=cos(arg);
Packit 06404a
  dsp=sin(arg);
Packit 06404a
  nbd=(ido-1)>>1;
Packit 06404a
  ipp2=ip;
Packit 06404a
  ipph=(ip+1)>>1;
Packit 06404a
  if(ido
Packit 06404a
Packit 06404a
  t1=0;
Packit 06404a
  t2=0;
Packit 06404a
  for(k=0;k
Packit 06404a
    t3=t1;
Packit 06404a
    t4=t2;
Packit 06404a
    for(i=0;i
Packit 06404a
      ch[t3]=cc[t4];
Packit 06404a
      t3++;
Packit 06404a
      t4++;
Packit 06404a
    }
Packit 06404a
    t1+=ido;
Packit 06404a
    t2+=t10;
Packit 06404a
  }
Packit 06404a
  goto L106;
Packit 06404a
Packit 06404a
 L103:
Packit 06404a
  t1=0;
Packit 06404a
  for(i=0;i
Packit 06404a
    t2=t1;
Packit 06404a
    t3=t1;
Packit 06404a
    for(k=0;k
Packit 06404a
      ch[t2]=cc[t3];
Packit 06404a
      t2+=ido;
Packit 06404a
      t3+=t10;
Packit 06404a
    }
Packit 06404a
    t1++;
Packit 06404a
  }
Packit 06404a
Packit 06404a
 L106:
Packit 06404a
  t1=0;
Packit 06404a
  t2=ipp2*t0;
Packit 06404a
  t7=(t5=ido<<1);
Packit 06404a
  for(j=1;j
Packit 06404a
    t1+=t0;
Packit 06404a
    t2-=t0;
Packit 06404a
    t3=t1;
Packit 06404a
    t4=t2;
Packit 06404a
    t6=t5;
Packit 06404a
    for(k=0;k
Packit 06404a
      ch[t3]=cc[t6-1]+cc[t6-1];
Packit 06404a
      ch[t4]=cc[t6]+cc[t6];
Packit 06404a
      t3+=ido;
Packit 06404a
      t4+=ido;
Packit 06404a
      t6+=t10;
Packit 06404a
    }
Packit 06404a
    t5+=t7;
Packit 06404a
  }
Packit 06404a
Packit 06404a
  if (ido == 1)goto L116;
Packit 06404a
  if(nbd
Packit 06404a
Packit 06404a
  t1=0;
Packit 06404a
  t2=ipp2*t0;
Packit 06404a
  t7=0;
Packit 06404a
  for(j=1;j
Packit 06404a
    t1+=t0;
Packit 06404a
    t2-=t0;
Packit 06404a
    t3=t1;
Packit 06404a
    t4=t2;
Packit 06404a
Packit 06404a
    t7+=(ido<<1);
Packit 06404a
    t8=t7;
Packit 06404a
    for(k=0;k
Packit 06404a
      t5=t3;
Packit 06404a
      t6=t4;
Packit 06404a
      t9=t8;
Packit 06404a
      t11=t8;
Packit 06404a
      for(i=2;i
Packit 06404a
        t5+=2;
Packit 06404a
        t6+=2;
Packit 06404a
        t9+=2;
Packit 06404a
        t11-=2;
Packit 06404a
        ch[t5-1]=cc[t9-1]+cc[t11-1];
Packit 06404a
        ch[t6-1]=cc[t9-1]-cc[t11-1];
Packit 06404a
        ch[t5]=cc[t9]-cc[t11];
Packit 06404a
        ch[t6]=cc[t9]+cc[t11];
Packit 06404a
      }
Packit 06404a
      t3+=ido;
Packit 06404a
      t4+=ido;
Packit 06404a
      t8+=t10;
Packit 06404a
    }
Packit 06404a
  }
Packit 06404a
  goto L116;
Packit 06404a
Packit 06404a
 L112:
Packit 06404a
  t1=0;
Packit 06404a
  t2=ipp2*t0;
Packit 06404a
  t7=0;
Packit 06404a
  for(j=1;j
Packit 06404a
    t1+=t0;
Packit 06404a
    t2-=t0;
Packit 06404a
    t3=t1;
Packit 06404a
    t4=t2;
Packit 06404a
    t7+=(ido<<1);
Packit 06404a
    t8=t7;
Packit 06404a
    t9=t7;
Packit 06404a
    for(i=2;i
Packit 06404a
      t3+=2;
Packit 06404a
      t4+=2;
Packit 06404a
      t8+=2;
Packit 06404a
      t9-=2;
Packit 06404a
      t5=t3;
Packit 06404a
      t6=t4;
Packit 06404a
      t11=t8;
Packit 06404a
      t12=t9;
Packit 06404a
      for(k=0;k
Packit 06404a
        ch[t5-1]=cc[t11-1]+cc[t12-1];
Packit 06404a
        ch[t6-1]=cc[t11-1]-cc[t12-1];
Packit 06404a
        ch[t5]=cc[t11]-cc[t12];
Packit 06404a
        ch[t6]=cc[t11]+cc[t12];
Packit 06404a
        t5+=ido;
Packit 06404a
        t6+=ido;
Packit 06404a
        t11+=t10;
Packit 06404a
        t12+=t10;
Packit 06404a
      }
Packit 06404a
    }
Packit 06404a
  }
Packit 06404a
Packit 06404a
L116:
Packit 06404a
  ar1=1.f;
Packit 06404a
  ai1=0.f;
Packit 06404a
  t1=0;
Packit 06404a
  t9=(t2=ipp2*idl1);
Packit 06404a
  t3=(ip-1)*idl1;
Packit 06404a
  for(l=1;l
Packit 06404a
    t1+=idl1;
Packit 06404a
    t2-=idl1;
Packit 06404a
Packit 06404a
    ar1h=dcp*ar1-dsp*ai1;
Packit 06404a
    ai1=dcp*ai1+dsp*ar1;
Packit 06404a
    ar1=ar1h;
Packit 06404a
    t4=t1;
Packit 06404a
    t5=t2;
Packit 06404a
    t6=0;
Packit 06404a
    t7=idl1;
Packit 06404a
    t8=t3;
Packit 06404a
    for(ik=0;ik
Packit 06404a
      c2[t4++]=ch2[t6++]+ar1*ch2[t7++];
Packit 06404a
      c2[t5++]=ai1*ch2[t8++];
Packit 06404a
    }
Packit 06404a
    dc2=ar1;
Packit 06404a
    ds2=ai1;
Packit 06404a
    ar2=ar1;
Packit 06404a
    ai2=ai1;
Packit 06404a
Packit 06404a
    t6=idl1;
Packit 06404a
    t7=t9-idl1;
Packit 06404a
    for(j=2;j
Packit 06404a
      t6+=idl1;
Packit 06404a
      t7-=idl1;
Packit 06404a
      ar2h=dc2*ar2-ds2*ai2;
Packit 06404a
      ai2=dc2*ai2+ds2*ar2;
Packit 06404a
      ar2=ar2h;
Packit 06404a
      t4=t1;
Packit 06404a
      t5=t2;
Packit 06404a
      t11=t6;
Packit 06404a
      t12=t7;
Packit 06404a
      for(ik=0;ik
Packit 06404a
        c2[t4++]+=ar2*ch2[t11++];
Packit 06404a
        c2[t5++]+=ai2*ch2[t12++];
Packit 06404a
      }
Packit 06404a
    }
Packit 06404a
  }
Packit 06404a
Packit 06404a
  t1=0;
Packit 06404a
  for(j=1;j
Packit 06404a
    t1+=idl1;
Packit 06404a
    t2=t1;
Packit 06404a
    for(ik=0;ik
Packit 06404a
  }
Packit 06404a
Packit 06404a
  t1=0;
Packit 06404a
  t2=ipp2*t0;
Packit 06404a
  for(j=1;j
Packit 06404a
    t1+=t0;
Packit 06404a
    t2-=t0;
Packit 06404a
    t3=t1;
Packit 06404a
    t4=t2;
Packit 06404a
    for(k=0;k
Packit 06404a
      ch[t3]=c1[t3]-c1[t4];
Packit 06404a
      ch[t4]=c1[t3]+c1[t4];
Packit 06404a
      t3+=ido;
Packit 06404a
      t4+=ido;
Packit 06404a
    }
Packit 06404a
  }
Packit 06404a
Packit 06404a
  if(ido==1)goto L132;
Packit 06404a
  if(nbd
Packit 06404a
Packit 06404a
  t1=0;
Packit 06404a
  t2=ipp2*t0;
Packit 06404a
  for(j=1;j
Packit 06404a
    t1+=t0;
Packit 06404a
    t2-=t0;
Packit 06404a
    t3=t1;
Packit 06404a
    t4=t2;
Packit 06404a
    for(k=0;k
Packit 06404a
      t5=t3;
Packit 06404a
      t6=t4;
Packit 06404a
      for(i=2;i
Packit 06404a
        t5+=2;
Packit 06404a
        t6+=2;
Packit 06404a
        ch[t5-1]=c1[t5-1]-c1[t6];
Packit 06404a
        ch[t6-1]=c1[t5-1]+c1[t6];
Packit 06404a
        ch[t5]=c1[t5]+c1[t6-1];
Packit 06404a
        ch[t6]=c1[t5]-c1[t6-1];
Packit 06404a
      }
Packit 06404a
      t3+=ido;
Packit 06404a
      t4+=ido;
Packit 06404a
    }
Packit 06404a
  }
Packit 06404a
  goto L132;
Packit 06404a
Packit 06404a
 L128:
Packit 06404a
  t1=0;
Packit 06404a
  t2=ipp2*t0;
Packit 06404a
  for(j=1;j
Packit 06404a
    t1+=t0;
Packit 06404a
    t2-=t0;
Packit 06404a
    t3=t1;
Packit 06404a
    t4=t2;
Packit 06404a
    for(i=2;i
Packit 06404a
      t3+=2;
Packit 06404a
      t4+=2;
Packit 06404a
      t5=t3;
Packit 06404a
      t6=t4;
Packit 06404a
      for(k=0;k
Packit 06404a
        ch[t5-1]=c1[t5-1]-c1[t6];
Packit 06404a
        ch[t6-1]=c1[t5-1]+c1[t6];
Packit 06404a
        ch[t5]=c1[t5]+c1[t6-1];
Packit 06404a
        ch[t6]=c1[t5]-c1[t6-1];
Packit 06404a
        t5+=ido;
Packit 06404a
        t6+=ido;
Packit 06404a
      }
Packit 06404a
    }
Packit 06404a
  }
Packit 06404a
Packit 06404a
L132:
Packit 06404a
  if(ido==1)return;
Packit 06404a
Packit 06404a
  for(ik=0;ik
Packit 06404a
Packit 06404a
  t1=0;
Packit 06404a
  for(j=1;j
Packit 06404a
    t2=(t1+=t0);
Packit 06404a
    for(k=0;k
Packit 06404a
      c1[t2]=ch[t2];
Packit 06404a
      t2+=ido;
Packit 06404a
    }
Packit 06404a
  }
Packit 06404a
Packit 06404a
  if(nbd>l1)goto L139;
Packit 06404a
Packit 06404a
  is= -ido-1;
Packit 06404a
  t1=0;
Packit 06404a
  for(j=1;j
Packit 06404a
    is+=ido;
Packit 06404a
    t1+=t0;
Packit 06404a
    idij=is;
Packit 06404a
    t2=t1;
Packit 06404a
    for(i=2;i
Packit 06404a
      t2+=2;
Packit 06404a
      idij+=2;
Packit 06404a
      t3=t2;
Packit 06404a
      for(k=0;k
Packit 06404a
        c1[t3-1]=wa[idij-1]*ch[t3-1]-wa[idij]*ch[t3];
Packit 06404a
        c1[t3]=wa[idij-1]*ch[t3]+wa[idij]*ch[t3-1];
Packit 06404a
        t3+=ido;
Packit 06404a
      }
Packit 06404a
    }
Packit 06404a
  }
Packit 06404a
  return;
Packit 06404a
Packit 06404a
 L139:
Packit 06404a
  is= -ido-1;
Packit 06404a
  t1=0;
Packit 06404a
  for(j=1;j
Packit 06404a
    is+=ido;
Packit 06404a
    t1+=t0;
Packit 06404a
    t2=t1;
Packit 06404a
    for(k=0;k
Packit 06404a
      idij=is;
Packit 06404a
      t3=t2;
Packit 06404a
      for(i=2;i
Packit 06404a
        idij+=2;
Packit 06404a
        t3+=2;
Packit 06404a
        c1[t3-1]=wa[idij-1]*ch[t3-1]-wa[idij]*ch[t3];
Packit 06404a
        c1[t3]=wa[idij-1]*ch[t3]+wa[idij]*ch[t3-1];
Packit 06404a
      }
Packit 06404a
      t2+=ido;
Packit 06404a
    }
Packit 06404a
  }
Packit 06404a
}
Packit 06404a
Packit 06404a
static void drftb1(int n, float *c, float *ch, float *wa, int *ifac){
Packit 06404a
  int i,k1,l1,l2;
Packit 06404a
  int na;
Packit 06404a
  int nf,ip,iw,ix2,ix3,ido,idl1;
Packit 06404a
Packit 06404a
  nf=ifac[1];
Packit 06404a
  na=0;
Packit 06404a
  l1=1;
Packit 06404a
  iw=1;
Packit 06404a
Packit 06404a
  for(k1=0;k1
Packit 06404a
    ip=ifac[k1 + 2];
Packit 06404a
    l2=ip*l1;
Packit 06404a
    ido=n/l2;
Packit 06404a
    idl1=ido*l1;
Packit 06404a
    if(ip!=4)goto L103;
Packit 06404a
    ix2=iw+ido;
Packit 06404a
    ix3=ix2+ido;
Packit 06404a
Packit 06404a
    if(na!=0)
Packit 06404a
      dradb4(ido,l1,ch,c,wa+iw-1,wa+ix2-1,wa+ix3-1);
Packit 06404a
    else
Packit 06404a
      dradb4(ido,l1,c,ch,wa+iw-1,wa+ix2-1,wa+ix3-1);
Packit 06404a
    na=1-na;
Packit 06404a
    goto L115;
Packit 06404a
Packit 06404a
  L103:
Packit 06404a
    if(ip!=2)goto L106;
Packit 06404a
Packit 06404a
    if(na!=0)
Packit 06404a
      dradb2(ido,l1,ch,c,wa+iw-1);
Packit 06404a
    else
Packit 06404a
      dradb2(ido,l1,c,ch,wa+iw-1);
Packit 06404a
    na=1-na;
Packit 06404a
    goto L115;
Packit 06404a
Packit 06404a
  L106:
Packit 06404a
    if(ip!=3)goto L109;
Packit 06404a
Packit 06404a
    ix2=iw+ido;
Packit 06404a
    if(na!=0)
Packit 06404a
      dradb3(ido,l1,ch,c,wa+iw-1,wa+ix2-1);
Packit 06404a
    else
Packit 06404a
      dradb3(ido,l1,c,ch,wa+iw-1,wa+ix2-1);
Packit 06404a
    na=1-na;
Packit 06404a
    goto L115;
Packit 06404a
Packit 06404a
  L109:
Packit 06404a
/*    The radix five case can be translated later..... */
Packit 06404a
/*    if(ip!=5)goto L112;
Packit 06404a
Packit 06404a
    ix2=iw+ido;
Packit 06404a
    ix3=ix2+ido;
Packit 06404a
    ix4=ix3+ido;
Packit 06404a
    if(na!=0)
Packit 06404a
      dradb5(ido,l1,ch,c,wa+iw-1,wa+ix2-1,wa+ix3-1,wa+ix4-1);
Packit 06404a
    else
Packit 06404a
      dradb5(ido,l1,c,ch,wa+iw-1,wa+ix2-1,wa+ix3-1,wa+ix4-1);
Packit 06404a
    na=1-na;
Packit 06404a
    goto L115;
Packit 06404a
Packit 06404a
  L112:*/
Packit 06404a
    if(na!=0)
Packit 06404a
      dradbg(ido,ip,l1,idl1,ch,ch,ch,c,c,wa+iw-1);
Packit 06404a
    else
Packit 06404a
      dradbg(ido,ip,l1,idl1,c,c,c,ch,ch,wa+iw-1);
Packit 06404a
    if(ido==1)na=1-na;
Packit 06404a
Packit 06404a
  L115:
Packit 06404a
    l1=l2;
Packit 06404a
    iw+=(ip-1)*ido;
Packit 06404a
  }
Packit 06404a
Packit 06404a
  if(na==0)return;
Packit 06404a
Packit 06404a
  for(i=0;i
Packit 06404a
}
Packit 06404a
Packit 06404a
void drft_forward(drft_lookup *l,float *data){
Packit 06404a
  if(l->n==1)return;
Packit 06404a
  drftf1(l->n,data,l->trigcache,l->trigcache+l->n,l->splitcache);
Packit 06404a
}
Packit 06404a
Packit 06404a
void drft_backward(drft_lookup *l,float *data){
Packit 06404a
  if (l->n==1)return;
Packit 06404a
  drftb1(l->n,data,l->trigcache,l->trigcache+l->n,l->splitcache);
Packit 06404a
}
Packit 06404a
Packit 06404a
void drft_init(drft_lookup *l,int n){
Packit 06404a
  l->n=n;
Packit 06404a
  l->trigcache=_ogg_calloc(3*n,sizeof(*l->trigcache));
Packit 06404a
  l->splitcache=_ogg_calloc(32,sizeof(*l->splitcache));
Packit 06404a
  fdrffti(n, l->trigcache, l->splitcache);
Packit 06404a
}
Packit 06404a
Packit 06404a
void drft_clear(drft_lookup *l){
Packit 06404a
  if(l){
Packit 06404a
    if(l->trigcache)_ogg_free(l->trigcache);
Packit 06404a
    if(l->splitcache)_ogg_free(l->splitcache);
Packit 06404a
    memset(l,0,sizeof(*l));
Packit 06404a
  }
Packit 06404a
}