#include<iostream.h>
#include<fstream.h>
#include<math.h>
#include<stdlib.h>

const int nbits=26;
const int nmax=1000;
const int nc=5;

void main(){
	int i, j, k, iter;
	double grad, delta=.0001;
	double I[nbits], Icanal[nbits], Ichap[nbits], c[nc], x[nc], err[nbits], err2[nmax], echo[4][nbits];
	double Itild[nbits], Ichapddm[nbits], cddm[nc], xddm[nc], errtddm[nbits], err2tddm[nmax], errddm[nbits], err2ddm[nmax];
	ofstream os;
	os.open("erreur.xls");
	os<<"Erreur\n";
	ofstream os2;
	os2.open("erreur2.xls");
	os2<<"Erreur\n";
	
	/************************************
	 *détermination séquence après canal*
	 ************************************/

	for(i=0;i<nbits;i++){
		double temp=(double)rand()/RAND_MAX;
		if(temp>=.5) I[i]=1;
		else I[i]=0;
		Icanal[i]=I[i];
		Ichap[i]=0;
	}
	for(j=0;j<nbits;j++){
		echo[0][j]=.3*I[j];
		echo[1][j]=.4*I[j];
		echo[2][j]=.7*I[j];
		echo[3][j]=.4*I[j];
	}
	for(i=0;i<4;i++){
		for(j=i+1;j<nbits;j++){
			Icanal[j]+=echo[i][j];	
		}
	}

	for(i=0;i<nbits;i++) Icanal[i]+=(2*(double)rand()/RAND_MAX-1);	


	/***************
	 *apprentissage*
	 ***************/

	for(i=0;i<nc;i++) c[i]=(double)rand()/RAND_MAX;
	
	for(iter=0;iter<nmax;iter++){
		err2[iter]=0;
		grad=0;
		for(j=0;j<nc;j++) x[j]=0;
		for(i=0;i<nbits;i++){
			for(k=0;k<nc;k++){
				if(k!=0) x[k]=x[k-1];
				x[0]=Icanal[i];
				Ichap[i]=c[0]*x[0]+c[1]*x[1]+c[2]*x[2]+c[3]*x[3]+c[4]*x[4];
			}
			err[i]=Ichap[i]-I[i];
			err2[iter]+=(err[i]*err[i]);
			grad+=err[i]*Icanal[i];
		}
		for(j=0;j<nc;j++) c[j]-=(delta*grad);
		os<<err2[iter]<<"\n";
	}
	os<<"I\tIcanal\tIchap\n";
	for(i=0;i<nbits;i++){
		if(Ichap[i]>=.5) Ichap[i]=1;
		else Ichap[i]=0;
		os<<I[i]<<"\t"<<Icanal[i]<<"\t"<<Ichap[i]<<"\n";
	}
	os<<"Coef\n";
	for(j=0;j<nc;j++) os<<c[j]<<"\n";
	os.close();


	/***************
	 *mode décision*
	 ***************/


	for(i=0;i<nc;i++) cddm[i]=(double)rand()/RAND_MAX;
	for(i=0;i<nbits;i++){
		double temp=(double)rand()/RAND_MAX;
		if(temp>=.5) I[i]=1;
		else I[i]=0;
		Icanal[i]=I[i];
		Itild[i]=0;
	}
	double signe[]={.01,-.01,.01,-.01};
	for(i=0;i<4;i++){
			for(j=i+1;j<nbits;j++){
				Icanal[j]+=echo[i][j];	
			}
		}
		for(i=0;i<nbits;i++) Icanal[i]+=(2*(double)rand()/RAND_MAX-1);

	for(iter=0;iter<nmax;iter++){
		err2ddm[iter]=0;
		err2tddm[iter]=0;
		grad=0;
		for(j=0;j<nc;j++) xddm[j]=0;
		for(i=0;i<nbits;i++){
			for(k=0;k<nc;k++){
				if(k!=0) xddm[k]=xddm[k-1];
				xddm[0]=Icanal[i];
				//Ichapddm[i]=cddm[0]*xddm[0]+cddm[1]*xddm[1]+cddm[2]*xddm[2]+cddm[3]*xddm[3]+cddm[4]*xddm[4];
				Ichapddm[i]=c[0]*xddm[0]+c[1]*xddm[1]+c[2]*xddm[2]+c[3]*xddm[3]+c[4]*xddm[4];
			}
			if(Ichapddm[i]>=.5) Itild[i]=1;
			errddm[i]=Ichapddm[i]-Itild[i];
			err2ddm[iter]+=(errddm[i]*errddm[i]);
			grad+=errddm[i]*Icanal[i];
		}
		for(i=0;i<4;i++){
			for(j=i+1;j<nbits;j++){
				Icanal[j]+=(signe[i]*echo[i][j]);	
			}
		}

		for(j=0;j<nc;j++) cddm[j]-=(delta*grad);
		os2<<err2ddm[iter]<<"\n";
	}
	os2<<"I\tIcanal\tItild\n";
	for(i=0;i<nbits;i++) os2<<I[i]<<"\t"<<Icanal[i]<<"\t"<<Itild[i]<<"\n";
	os2<<"Coef\n";
	for(j=0;j<nc;j++) os2<<cddm[j]<<"\n";
	os.close();
	os2.close();

}