int mergecb(float *B,float **cb,unsigned char *P,int npt,int N,float thresh,int dim)
{
int i,j,newN,*count,l,ei,debug=0;
float **dist;
if (N==1) return N;
count=(int *)malloc(sizeof(int)*N);
for (l=0;l<npt;l++) count[P[l]]++;
dist=(float **)fmatrix(N,N);
ei = N-1;
for (i=0;i<ei;i++)
{
for (j=i+1;j<N;j++)
{
dist[i][j] = distance2(cb[i],cb[j],dim);
dist[j][i] = dist[i][j];
}
}
if (debug) printf("thresh %f ",thresh);
newN=mergecb1(dist,B,cb,N,thresh,dim,count);
free_fmatrix(dist,N);
free(count);
return newN;
}
int mergecb(float *B,float **cb,unsigned char *P,int npt,int N,float thresh,int dim)
{
int i,j,newN,*count,l,ei,*count2;
float **dist,**dist2,**cb2;
if (N==1) return 1;
count=(int *)calloc(N,sizeof(int));
for (l=0;l<npt;l++) count[P[l]]++;
dist=(float **)fmatrix(N,N);
ei = N-1;
for (i=0;i<ei;i++)
{
for (j=i+1;j<N;j++)
{
dist[i][j] = distance2(cb[i],cb[j],dim);
dist[j][i] = dist[i][j];
}
}
if (thresh<0)
{
cb2 = (float **)fmatrix(N,dim);
for (i=0;i<N;i++)
for (j=0;j<dim;j++) cb2[i][j]=cb[i][j];
count2=(int *)calloc(N,sizeof(int));
for (i=0;i<N;i++) count2[i]=count[i];
dist2=(float **)fmatrix(N,N);
for (i=0;i<N;i++)
for (j=0;j<N;j++) dist2[i][j]=dist[i][j];
if (dim==3) thresh=400;
else if (dim==1) thresh=800;
mergecb1(dist2,B,cb2,P,npt,N,&thresh,dim,count2,1);
free_fmatrix(cb2,N);
free(count2);
free_fmatrix(dist2,N);
}
printf("thresh %f ",thresh);
newN=mergecb1(dist,B,cb,P,npt,N,&thresh,dim,count,0);
free_fmatrix(dist,N);
free(count);
return newN;
}
/* Alloue de l'espace en mémoire pour créer une nouvelle matrice.
* lin et col indiquent le nombre de lignes et de colonnes respectivement.
*
* Renvoie un pointeur vers la matrice. En cas d'erreur, retourne NULL.
*/
fmatrix *allocate_fmatrix(long lin, long col) {
/* Vérifie que les dimensions sont cohérentes */
if ((lin < 1) || (col < 1)) {
fprintf(stderr, "Error calling allocate_fmatrix :"
" your fmatrix has dimensions %ldx%ld\n", lin, col);
return NULL;
}
/* Crée la matrice */
fmatrix *mat = (fmatrix *)malloc(sizeof(fmatrix));
if (!mat) {
fprintf(stderr, "Error calling allocate_fmatrix :"
" malloc failed\n");
return NULL;
}
/* Crée le tableau */
long **tab = (long **)malloc(lin*sizeof(long *));
if (!tab) {
fprintf(stderr, "Error calling allocate_fmatrix :"
" malloc failed\n");
return NULL;
}
/* Initialisation de toutes les listes chaînées */
long i;
for (i=0; i<lin; i++) {
tab[i] = (long *)malloc(col*sizeof(long));
if (!tab[i]) {
fprintf(stderr, "Error calling allocate_fmatrix :"
" malloc to initialize line %ld failed\n", i);
free_fmatrix(mat);
return NULL;
}
}
/* Données de la matrice */
mat->n = lin;
mat->m = col;
mat->pointers = tab;
/* Retourne une matrice initialisée */
return mat;
}
int greedy(float *A,int nvec,int ndim,int N,float **codebook,float t,unsigned char *P,
float *weight)
{
int iv,in,jn,imax,nsplit,*index2,k,i,retgla,kn;
float *totalw,*d,**buf, *variance;
buf=fmatrix(N,ndim);
d=(float *)calloc(ndim,sizeof(float));
variance=(float *)calloc(N,sizeof(float));
totalw=(float *)calloc(N,sizeof(float));
index2=(int *)calloc(N,sizeof(int));
/* Calculate the initial centroid */
for (k=0;k<ndim;k++) codebook[0][k]=0.0;
totalw[0]=0; i=0;
for (iv=0;iv<nvec;iv++)
{
P[iv]= 0;
totalw[0]+=weight[iv];
for (k=0;k<ndim;k++) codebook[0][k] += weight[iv]*A[i++];
}
for (k=0;k<ndim;k++) codebook[0][k]/=totalw[0];
in=1;
while (in<N)
{
/* find the maximum variance */
for (jn=0;jn<in;jn++)
{
variance[jn]=0;
totalw[jn]=0;
for (k=0;k<ndim;k++) buf[jn][k]=0.0;
}
i = 0;
for (iv=0;iv<nvec;iv++)
{
for (k=0;k<ndim;k++) d[k] = codebook[P[iv]][k] - A[i++];
for (k=0;k<ndim;k++)
{
buf[P[iv]][k] += weight[iv]*sqr(d[k]);
variance[P[iv]]+= buf[P[iv]][k];
}
totalw[P[iv]] += weight[iv];
}
for (jn=0;jn<in;jn++)
{
for (k=0;k<ndim;k++) buf[jn][k] = sqrt(buf[jn][k]/totalw[jn]);
}
piksrt(in,variance,index2);
/* split */
nsplit=in/2+1;
if ((nsplit+in)>N) nsplit=N-in;
for (jn=0;jn<nsplit;jn++)
{
imax=index2[jn];
for (k=0;k<ndim;k++) codebook[in+jn][k] = codebook[imax][k] - buf[imax][k];
for (k=0;k<ndim;k++) codebook[imax] [k] = codebook[imax][k] + buf[imax][k];
}
/* run gla on the codebook */
in=in+nsplit;
retgla=gla(A,nvec,ndim,in,codebook,t,P,weight);
/* find the code vectors same, remove them and stop */
if (retgla)
{
for (jn=0;jn<in-1;jn++)
{
for (kn=jn+1;kn<in;kn++)
{
if (distance2(codebook[jn],codebook[kn],ndim)==0)
{
for (i=kn;i<in-1;i++)
for (k=0;k<ndim;k++) codebook[i][k]=codebook[i+1][k];
in--;
}
}
}
break;
}
}
free_fmatrix(buf,N);
free (d);
free (index2);
free(variance);
free(totalw);
return in;
}
