//####################################################################//MILCA//####################################################################//2 May 2004//Contact: kraskov@its.caltech.edu//####################################################################//uses mi2c mi2r#include <stdio.h>#include <stdlib.h>#include <string.h>#include <math.h>#include <float.h>#include "miutils.h"#define M 7#define NSTACK 50#define SWAP(a,b) tempr=(a); (a)=(b); (b)=temprvoid four1(double *data, unsigned long nn, int isign);void realft(double *data, unsigned long n, int isign);int main(int argc, char **argv) {  FILE *fin;  int i,d,d1,d2, d_,d2_;  int N=4096;;  int dim=3;  int K=1;  double **x;  double **xx;  double *psi,*min,*max,*scalxx;  double t_d,t_d1;  int BOX1;  double s,me;  int k;  double *rmi;  double angle;  double st_d, ct_d;  double **Rall,**R,**Rt;  int p, pMax;  int count;  int ns=1;  double mimin;  int angI;  int method=1;  int nr=128;  double addnoise=-1;    if (argc<5) {    fprintf(stderr,"\nMutual Information Least dependent Component Analysis (MILCA)\n\n");    fprintf(stderr,"Usage:\n%s <filename> <dim> <# points> <# neighbours> [method] [nrot] [nharm] [addnoise]\n\n",argv[0]);    fprintf(stderr,"Input:\n\t<filename>\ttext file with <dim> columns and <# points> rows\n");    fprintf(stderr,"\t<dim>\t\tnumber of columns in file\n");    fprintf(stderr,"\t<# points>\tnumber of rows (length of characteristic vector)\n");    fprintf(stderr,"\t<# neighbours>\tnumber of the nearest neighbours for MI estimator\n");    fprintf(stderr,"\t[method]\teither cubic (0), or rectangular (1); default 1\n");    fprintf(stderr,"\t[nrot]\t\tnumber of angles to minimize over; default 128\n");    fprintf(stderr,"\t[nharm]\t\tnumber of harmonics to approximate MI(angle) dependence; default 1\n");    fprintf(stderr,"\t[addnoise]\tnoise amplitude; default 1e-8\n");    fprintf(stderr,"\nOutput:\n");    fprintf(stderr,"\nde-mixing matrix\n");    fprintf(stderr,"\nContact: kraskov@its.caltech.edu\n");    exit(-1);  }  dim=atoi(argv[2]);  N=atoi(argv[3]);  K=atoi(argv[4]);  if (argc>=6) method=atoi(argv[5]);  if (argc>=7) nr=atoi(argv[6]);  if (argc>=8) ns=atoi(argv[7]);  if (argc>=9) addnoise=atof(argv[8]);  if (argc>=10) {fprintf(stderr,"Too many input arguments\n");exit(-1);}  pMax=dim-1;  rmi=(double *)calloc(nr+1,sizeof(double));  xx=(double **)calloc(2,sizeof(double*));  xx[0]=(double *)calloc(N,sizeof(double));  xx[1]=(double *)calloc(N,sizeof(double));  x=(double **)calloc(dim,sizeof(double*));  for (d=0;d<dim;d++) {    x[d]=(double *)calloc(N,sizeof(double));  }  Rall=(double **)calloc(dim,sizeof(double*));  R=(double **)calloc(dim,sizeof(double*));  for (d=0;d<dim;d++) {    Rall[d]=(double *)calloc(dim,sizeof(double));    R[d]=(double *)calloc(dim,sizeof(double));    for (d2=0;d2<dim;d2++) Rall[d][d2]=(d==d2);  }  Rt=(double **)calloc(2,sizeof(double*));  Rt[0]=(double *)calloc(dim,sizeof(double));  Rt[1]=(double *)calloc(dim,sizeof(double));  //reading of the data  fin=fopen(argv[1],"r");  if (fin)    for (i=0;i<N;i++) {      for (d=0;d<dim;d++) {	fscanf(fin,"%lf",&(x[d][i]));      }    }  else { fprintf(stderr,"File %s doesn't exist\n",argv[1]);exit(-1);}  fclose(fin);  // add noise  if (addnoise) {    srand((dim)*N*K*int(x[(dim)/2][N/10]));    if (addnoise==-1) for (d=0;d<dim;d++) for (i=0;i<N;i++) x[d][i]+=(1.0*rand()/RAND_MAX)*1e-8;    else for (d=0;d<dim;d++) for (i=0;i<N;i++) x[d][i]+=(1.0*rand()/RAND_MAX)*addnoise;  }  min=(double*)calloc(dim,sizeof(double));  max=(double*)calloc(dim,sizeof(double));  //normalization  for (d=0;d<dim;d++) {    me=s=0; for (i=0;i<N;i++) me+=x[d][i];    me/=N;  for (i=0;i<N;i++) s+=(x[d][i]-me)*(x[d][i]-me);    s/=(N-1);s=sqrt(s);     if (s==0) {;}    for (i=0;i<N;i++) {      x[d][i] = (x[d][i]-me)/s;      if (x[d][i]<min[d]) min[d]=x[d][i];       if (x[d][i]>max[d]) max[d]=x[d][i];    }    for (i=0;i<N;i++) x[d][i]=x[d][i]-min[d];  }  psi=(double*)calloc(N+1,sizeof(double));  psi[1]=-(double).57721566490153;  for (i=1;i<N;i++) psi[i+1]=psi[i]+1/(double)i; //cubic  BOX1=N-5;  scalxx=(double*)calloc(2,sizeof(double));  count=0;  for (p=0;p<pMax;p++) {    for (d=0;d<dim;d++) {      for (d2=0;d2<dim;d2++) {	if ( (d<d2) || ((dim>2) && (d!=d2)) ) {	  for (k=0;k<nr;k++) {	    angle=1.0*k/nr*M_PI/2;	    st_d=sin(angle);ct_d=cos(angle);	    for (i=0;i<N;i++) {	      t_d=x[d][i];t_d1=x[d2][i];	      xx[0][i]=ct_d*t_d+st_d*t_d1;	      xx[1][i]=ct_d*t_d1-st_d*t_d;	    }	    for (d1=0;d1<2;d1++) {min[d1]=DBL_MAX/2;max[d1]=-DBL_MAX/2;}	    for (d1=0;d1<2;d1++) {	      for (i=0;i<N;i++) {		if (xx[d1][i]<min[d1]) min[d1]=xx[d1][i];		if (xx[d1][i]>max[d1]) max[d1]=xx[d1][i];	      }	      for (i=0;i<N;i++) xx[d1][i]=xx[d1][i]-min[d1];	    }	    for (d1=0;d1<2;d1++) scalxx[d1]=BOX1/(max[d1]-min[d1]);	    switch (method) {	    case 0 :  mi2c(xx,N,K,psi,scalxx,&(rmi[k])); break;	    case 1 :  mi2r(xx,N,K,psi,scalxx,&(rmi[k])); break;	    }	  }	  realft(rmi-1,nr,1);//	  rmi[0]=0;rmi[1]=0;	  for (k=2+ns*2;k<nr;k++) rmi[k]=0;	  realft(rmi-1,nr,-1);	  mimin=rmi[0];angI=0;	  for (k=1;k<nr;k++) {	    if (rmi[k]<mimin) {	      mimin=rmi[k];angI=k;	    }	  }	  angle=1.0*angI/nr*M_PI/2;	  //fprintf(stdout,"i=%d, j=%d \t p=%d, angle %1.6f\n",d,d2,p,angle);	  	  if ( (angI>=1) && (angI<=nr-1) ) {//minumin angle rotation are too small, and not considered	    for (d_=0;d_<dim;d_++) for (d2_=0;d2_<dim;d2_++) R[d_][d2_]=(d_==d2_);	    	    st_d=sin(angle);ct_d=cos(angle);	    	    R[d][d]=ct_d;	    R[d][d2]=st_d;	    R[d2][d]=-st_d;	    R[d2][d2]=ct_d;	    for (i=0;i<N;i++) {	      t_d=x[d][i];t_d1=x[d2][i];	      x[d][i]=ct_d*t_d+st_d*t_d1;	      x[d2][i]=ct_d*t_d1-st_d*t_d;	    }	    for (d_=0;d_<dim;d_++) {	      Rt[0][d_]=0;Rt[1][d_]=0;	      for (d2_=0;d2_<dim;d2_++) {		Rt[0][d_]+=R[d][d2_]*Rall[d2_][d_];		Rt[1][d_]+=R[d2][d2_]*Rall[d2_][d_];	      }	    }	    memcpy(Rall[d],Rt[0],dim*sizeof(double));	    memcpy(Rall[d2],Rt[1],dim*sizeof(double));	    count++;	  }	}      }    }          if (dim==2) break;    if (count==0) break;    count=0;  }  //output  for (d=0;d<dim;d++) {    for (d2=0;d2<dim;d2++) {      fprintf(stdout,"%f\t",Rall[d][d2]);    }    fprintf(stdout,"\n");  }  free(rmi);  free(xx[0]);free(xx[1]);free(xx);  for (d=0;d<dim;d++) {    free(Rall[d]);free(R[d]);free(x[d]);  }  free(Rall);free(R);free(x);  free(Rt[0]);free(Rt[1]);free(Rt);  free(min);  free(max);  free(psi);  free(scalxx);}void four1(double *data, unsigned long nn, int isign)  // The length of data should be 2*nn, because data is complex array  // nn - number of complex points{  unsigned long n,mmax,m,j,istep,i;  double wtemp,wr,wpr,wpi,wi,theta;  double tempr,tempi;    n=nn << 1;  j=1;  for (i=1;i<n;i+=2) {    if (j > i) {      SWAP(data[j],data[i]);      SWAP(data[j+1],data[i+1]);    }    m=n >> 1;    while (m >= 2 && j > m) {      j -= m;      m >>= 1;    }    j += m;  }  mmax=2;  while (n > mmax) {    istep=mmax << 1;    theta=isign*(6.28318530717959/mmax);    wtemp=sin(0.5*theta);    wpr = -2.0*wtemp*wtemp;    wpi=sin(theta);    wr=1.0;    wi=0.0;    for (m=1;m<mmax;m+=2) {      for (i=m;i<=n;i+=istep) {        j=i+mmax;        tempr=wr*data[j]-wi*data[j+1];        tempi=wr*data[j+1]+wi*data[j];        data[j]=data[i]-tempr;        data[j+1]=data[i+1]-tempi;        data[i] += tempr;        data[i+1] += tempi;      }      wr=(wtemp=wr)*wpr-wi*wpi+wr;      wi=wi*wpr+wtemp*wpi+wi;    }    mmax=istep;  }}/* (C) Copr. 1986-92 Numerical Recipes Software -0)0+3$j3D.. */void realft(double *data, unsigned long n, int isign) {   //Calculates the Fourier transform of a set of n real-valued data  //points. Replaces this data (which is stored in array data[1..n]) by  //the positive frequency half of its complex Fourier transform. The  //real-valued  rst and last components of the complex transform are  //returned as elements data[1] and data[2], respectively. n must be a  //power of 2. This routine also calculates the inverse transform of a  //complex data array if it is the transform of real data. (Result in  //this case must be multiplied by 2/n.)  unsigned long i,i1,i2,i3,i4,np3;  double c1=0.5,c2,h1r,h1i,h2r,h2i;  double wr,wi,wpr,wpi,wtemp,theta;    theta=M_PI/(double)(n>>1);  if (isign == 1) {    c2 = -0.5;    four1(data,n>>1,1);  } else {    c2=0.5;    theta = -theta;  }  wtemp=sin(0.5*theta);  wpr = -2.0*wtemp*wtemp;  wpi=sin(theta);  wr=1.0+wpr;  wi=wpi;  np3=n+3;  for (i=2;i<=(n>>2);i++) {    i4=1+(i3=np3-(i2=1+(i1=i+i-1)));    h1r=c1*(data[i1]+data[i3]);    h1i=c1*(data[i2]-data[i4]);    h2r = -c2*(data[i2]+data[i4]);    h2i=c2*(data[i1]-data[i3]);    data[i1]=h1r+wr*h2r-wi*h2i;    data[i2]=h1i+wr*h2i+wi*h2r;    data[i3]=h1r-wr*h2r+wi*h2i;    data[i4] = -h1i+wr*h2i+wi*h2r;    wr=(wtemp=wr)*wpr-wi*wpi+wr;    wi=wi*wpr+wtemp*wpi+wi;  }  if (isign == 1) {    data[1] = (h1r=data[1])+data[2];    data[2] = h1r-data[2];  } else {    data[1]=c1*((h1r=data[1])+data[2]);    data[2]=c1*(h1r-data[2]);    four1(data,n>>1,-1);  }}/* (C) Copr. 1986-92 Numerical Recipes Software -0)0+3$j3D.. */