void gmm_fisher_save_soft_assgn(int n, const float *v, const gmm_t * g, int flags,
float *dp_dlambda,
float *word_total_soft_assignment) {
long d=g->d, k=g->k;
float *p = fvec_new(n * k);
long i,j,l;
long ii=0;
float * vp = NULL; /* v*p */
float * sum_pj = NULL; /* sum of p's for a given j */
gmm_compute_p(n,v,g,p,flags | GMM_FLAGS_W);
#define P(j,i) p[(i)*k+(j)]
#define V(l,i) v[(i)*d+(l)]
#define MU(l,j) g->mu[(j)*d+(l)]
#define SIGMA(l,j) g->sigma[(j)*d+(l)]
#define VP(l,j) vp[(j)*d+(l)]
// Save total soft assignment per centroid
if (word_total_soft_assignment != NULL) {
for (j=0; j<k; j++) {
double sum=0;
for (i=0; i<n; i++) {
sum += P(j,i);
}
if (n != 0) {
word_total_soft_assignment[j] = (float)(sum/n);
} else {
word_total_soft_assignment[j] = 0.0;
}
}
}
if(flags & GMM_FLAGS_W) {
for(j=1; j<k; j++) {
double accu=0;
for(i=0; i<n; i++)
accu+= P(j,i)/g->w[j] - P(0,i)/g->w[0];
/* normalization */
double f=n*(1/g->w[j]+1/g->w[0]);
dp_dlambda[ii++]=accu/sqrt(f);
}
}
if(flags & GMM_FLAGS_MU) {
float *dp_dmu=dp_dlambda+ii;
#define DP_DMU(l,j) dp_dmu[(j)*d+(l)]
if(0) { /* simple and slow */
for(j=0; j<k; j++) {
for(l=0; l<d; l++) {
double accu=0;
for(i=0; i<n; i++)
accu += P(j,i) * (V(l,i)-MU(l,j)) / SIGMA(l,j);
DP_DMU(l,j)=accu;
}
}
} else { /* complicated and fast */
/* precompute tables that may be useful for sigma too */
vp = fvec_new(k * d);
fmat_mul_tr(v,p,d,k,n,vp);
sum_pj = fvec_new(k);
for(j=0; j<k; j++) {
double sum=0;
for(i=0; i<n; i++) sum += P(j,i);
sum_pj[j] = sum;
}
for(j=0; j<k; j++) {
for(l=0; l<d; l++)
DP_DMU(l,j) = (VP(l,j) - MU(l,j) * sum_pj[j]) / SIGMA(l,j);
}
}
/* normalization */
if(!(flags & GMM_FLAGS_NO_NORM)) {
for(j=0; j<k; j++)
for(l=0; l<d; l++) {
float nf = sqrt(n*g->w[j]/SIGMA(l,j));
if(nf > 0) DP_DMU(l,j) /= nf;
}
}
#undef DP_DMU
ii+=d*k;
}
if(flags & (GMM_FLAGS_SIGMA | GMM_FLAGS_1SIGMA)) {
if(flags & GMM_FLAGS_1SIGMA) { /* fast not implemented for 1 sigma */
for(j=0; j<k; j++) {
double accu2=0;
for(l=0; l<d; l++) {
double accu=0;
for(i=0; i<n; i++)
accu += P(j,i) * (sqr(V(l,i)-MU(l,j)) / SIGMA(l,j) - 1) / sqrt(SIGMA(l,j));
if(flags & GMM_FLAGS_SIGMA) {
double f=flags & GMM_FLAGS_NO_NORM ? 1.0 : 2*n*g->w[j]/SIGMA(l,j);
dp_dlambda[ii++]=accu/sqrt(f);
}
accu2+=accu;
}
if(flags & GMM_FLAGS_1SIGMA) {
double f=flags & GMM_FLAGS_NO_NORM ? 1.0 : 2*d*n*g->w[j]/SIGMA(0,j);
dp_dlambda[ii++]=accu2/sqrt(f);
}
}
} else { /* fast and complicated */
assert(flags & GMM_FLAGS_SIGMA);
float *dp_dsigma = dp_dlambda + ii;
if(!vp) {
vp = fvec_new(k * d);
fmat_mul_tr(v,p,d,k,n,vp);
}
if(!sum_pj) {
sum_pj = fvec_new(k);
for(j=0; j<k; j++) {
double sum=0;
for(i=0; i<n; i++) sum += P(j,i);
sum_pj[j] = sum;
}
}
float *v2 = fvec_new(n * d);
for(i = n*d-1 ; i >= 0; i--) v2[i] = v[i] * v[i];
float *v2p = fvec_new(k * d);
fmat_mul_tr(v2,p,d,k,n,v2p);
free(v2);
#define V2P(l,j) v2p[(j)*d+(l)]
#define DP_DSIGMA(i,j) dp_dsigma[(i)+(j)*d]
for(j=0; j<k; j++) {
for(l=0; l<d; l++) {
double accu;
accu = V2P(l, j);
accu += VP(l, j) * (- 2 * MU(l,j));
accu += sum_pj[j] * (sqr(MU(l,j)) - SIGMA(l,j));
/* normalization */
double f;
if(flags & GMM_FLAGS_NO_NORM) {
f = pow(SIGMA(l,j), -1.5);
} else {
f = 1 / (SIGMA(l,j) * sqrt(2*n*g->w[j]));
}
DP_DSIGMA(l,j) = accu * f;
}
}
free(v2p);
#undef DP_DSIGMA
#undef V2P
ii += d * k;
}
}
assert(ii==gmm_fisher_sizeof(g,flags));
#undef P
#undef V
#undef MU
#undef SIGMA
free(p);
free(sum_pj);
free(vp);
}
float *fmat_new_pca_from_covariance(int d,const float *cov, float *singvals)
{
float *pcamat=fvec_new(d*d);
fmat_pca_from_covariance (d, cov, singvals, pcamat);
return pcamat;
}
int main (int argc, char ** argv)
{
int i;
int k = 10;
int d = 0;
int nb = 0;
int nq = 0;
int nt = count_cpu();
int verbose = 1;
int ret = 0;
int fmt_b = FMT_FVEC;
int fmt_q = FMT_FVEC;
int fmt_nn = FMT_IVEC;
int fmt_dis = FMT_FVEC;
const char * fb_name = NULL; /* database filename */
const char * fq_name = NULL; /* query filename */
const char * fnn_name = "nn.out"; /* nn idx filename */
const char * fdis_name = "dis.out"; /* nn dis filename */
if (argc == 1)
usage (argv[0]);
for (i = 1 ; i < argc ; i++) {
char *a = argv[i];
if (!strcmp (a, "-h") || !strcmp (a, "--help"))
usage (argv[0]);
else if (!strcmp (a, "-silence")) {
verbose = 0;
}
else if (!strcmp (a, "-verbose")) {
verbose = 2;
}
else if (!strcmp (a, "-k") && i+1 < argc) {
ret = sscanf (argv[++i], "%d", &k);
assert (ret);
}
else if (!strcmp (a, "-d") && i+1 < argc) {
ret = sscanf (argv[++i], "%d", &d);
assert (ret);
}
else if (!strcmp (a, "-nt") && i+1 < argc) {
ret = sscanf (argv[++i], "%d", &nt);
assert (ret);
}
else if (!strcmp (a, "-nb") && i+1 < argc) {
ret = sscanf (argv[++i], "%d", &nb);
assert (ret);
}
else if (!strcmp (a, "-nq") && i+1 < argc) {
ret = sscanf (argv[++i], "%d", &nq);
assert (ret);
}
else if (!strcmp (a, "-b") && i+1 < argc) {
fb_name = argv[++i];
fmt_b = FMT_FVEC;
}
else if (!strcmp (a, "-bb") && i+1 < argc) {
fb_name = argv[++i];
fmt_b = FMT_BVEC;
}
else if (!strcmp (a, "-bt") && i+1 < argc) {
fb_name = argv[++i];
fmt_b = FMT_TEXT;
}
else if (!strcmp (a, "-q") && i+1 < argc) {
fq_name = argv[++i];
fmt_q = FMT_FVEC;
}
else if (!strcmp (a, "-qb") && i+1 < argc) {
fq_name = argv[++i];
fmt_q = FMT_BVEC;
}
else if (!strcmp (a, "-qt") && i+1 < argc) {
fq_name = argv[++i];
fmt_q = FMT_TEXT;
}
else if (!strcmp (a, "-onn") && i+1 < argc) {
fnn_name = argv[++i];
fmt_nn = FMT_IVEC;
}
else if (!strcmp (a, "-onnt") && i+1 < argc) {
fnn_name = argv[++i];
fmt_nn = FMT_TEXT;
}
else if (!strcmp (a, "-odis") && i+1 < argc) {
fdis_name = argv[++i];
fmt_dis = FMT_FVEC;
}
else if (!strcmp (a, "-odist") && i+1 < argc) {
fdis_name = argv[++i];
fmt_dis = FMT_TEXT;
}
}
assert (fb_name && fq_name);
fprintf (stderr, "k = %d\nd = %d\nnt = %d\n", k, d, nt);
if (verbose) {
fprintf (stderr, "fb = %s (fmt = %s)\n", fb_name,
(fmt_b == FMT_FVEC ? "fvec" : (fmt_b == FMT_BVEC ? "bvec" : "txt")));
fprintf (stderr, "fq = %s (fmt = %s)\n", fq_name,
(fmt_q == FMT_FVEC ? "fvec" : (fmt_q == FMT_BVEC ? "bvec" : "txt")));
fprintf (stderr, "fnn = %s (fmt = %s)\n", fnn_name,
(fmt_nn == FMT_IVEC ? "ivec" : "txt"));
fprintf (stderr, "fdis = %s (fmt = %s)\n", fdis_name,
(fmt_dis == FMT_FVEC ? "fvec" : "txt"));
}
/* read the input vectors for database and queries */
float * vb = my_fvec_read (fb_name, fmt_b, verbose, &nb, &d);
float * vq = my_fvec_read (fq_name, fmt_q, verbose, &nq, &d);
/* Search */
int * idx = ivec_new (k * nq);
float * dis = fvec_new (k * nq);
knn_full_thread (2, nq, nb, d, k, vb, vq, NULL, idx, dis, nt);
knn_reorder_shortlist (nq, nb, d, k, vb, vq, idx, dis);
/* write the distance output file */
if (fmt_dis == FMT_FVEC)
ret = fvecs_write (fdis_name, k, nq, dis);
else if (fmt_dis == FMT_TEXT)
ret = fvecs_write_txt (fdis_name, k, nq, dis);
else assert (0 || "Unknow output format\n");
assert (ret == nq);
/* write the distance output file */
if (fmt_nn == FMT_IVEC)
ret = ivecs_write (fnn_name, k, nq, idx);
else if (fmt_nn == FMT_TEXT)
ret = ivecs_write_txt (fnn_name, k, nq, idx);
else assert (0 || "Unknow output format\n");
assert (ret == nq);
free (idx);
free (dis);
free (vb);
free (vq);
return 0;
}
gmm_t * gmm_learn (int di, int ni, int ki, int niter,
const float * v, int nt, int seed, int nredo,
int flags)
{
long d=di,k=ki,n=ni;
int iter, iter_tot = 0;
double old_key, key = 666;
niter = (niter == 0 ? 10000 : niter);
/* the GMM parameters */
float * p = fvec_new_0 (n * k); /* p(ci|x) for all i */
gmm_t * g = gmm_new (d, k);
/* initialize the GMM: k-means + variance estimation */
int * nassign = ivec_new (n); /* not useful -> to be removed when debugged */
float * dis = fvec_new (n);
kmeans (d, n, k, niter, v, nt, seed, nredo, g->mu, dis, NULL, nassign);
fflush (stderr);
fprintf (stderr, "assign = ");
ivec_print (nassign, k);
fprintf (stderr, "\n");
free (nassign);
/* initialization of the GMM parameters assuming a diagonal matrix */
fvec_set (g->w, k, 1.0 / k);
double sig = fvec_sum (dis, n) / n;
printf ("sigma at initialization = %.3f\n", sig);
fvec_set (g->sigma, k * d, sig);
free (dis);
/* start the EM algorithm */
fprintf (stdout, "<><><><> GMM <><><><><>\n");
if(flags & GMM_FLAGS_PURE_KMEANS) niter=0;
for (iter = 1 ; iter <= niter ; iter++) {
gmm_compute_p_thread (n, v, g, p, flags, nt);
fflush(stdout);
gmm_handle_empty(n, v, g, p);
gmm_compute_params (n, v, p, g, flags, nt);
fflush(stdout);
iter_tot++;
/* convergence reached -> leave */
old_key = key;
key = fvec_sum (g->mu, k * d);
printf ("keys %5d: %.6f -> %.6f\n", iter, old_key, key);
fflush(stdout);
if (key == old_key)
break;
}
fprintf (stderr, "\n");
free(p);
return g;
}
float * fvec_new_cpy (const float * v, long n) {
float *ret = fvec_new(n);
memcpy (ret, v, n * sizeof (*ret));
return ret;
}
float * fvec_new_randn (long n)
{
float * f = fvec_new (n);
fvec_randn(f,n);
return f;
}
void ahc_clustering(DyArray *ahct, int bf, int rho, const fDataSet *ds){
ASSERTINFO(ahct == NULL || bf <= 0 || rho <= 0 || ds == NULL, "IPP");
int n = ds->n;
int d = ds->d;
Cluster _clu, clu, *pclu = NULL, *p0clu = NULL;
int i;
float qerror;
int iclu, bfi, ni, ichild, ori_id; // the pointer, branch factor and volume of the i-th cluster
int *nassign = ivec_new_set(bf, 0);
int *assign = NULL;
float *cent = fvec_new(d*bf);
float *mem_points = NULL;
DyArray *member = (DyArray*)malloc(sizeof(DyArray)*bf);
/* initialize the first cluster (root) to add it to the ahc tree */
Cluster_init(&clu, n);
for(i = 0; i < n; i++){
clu.idx[i] = i;
}
clu.type = ClusterType_Root;
DyArray_add(ahct, (void*)&clu, 1);
/* begin the loop of adaptive hierarchical clustering */
iclu = 0;
while(iclu < ahct->count){
/* deal with the i-th cluster */
// figure out the adaptive branch factor of the i-th cluster
pclu = (Cluster*)DyArray_get(ahct, iclu, 1);
ni = pclu->npts;
bfi = i_min(bf, (int)round(ni / (float)rho));
// deal with the cluster according to its size
if(bfi < 2){
/*
* this is a leaf cluster
* - mark it, release the children
* * not necessary to store real data points
*/
pclu->type = ClusterType_Leaf;
}else{
printf("----------------- cluster %d, bfi-%d:\n", iclu, bfi);
/*
* this is an inner cluster
* - divide it
*/
memcpy(&_clu, pclu, sizeof(Cluster));
// extract data points from the original dataset according to the idx
mem_points = fvec_new(ni * d);
for(i = 0; i < ni; i++){
memcpy(mem_points+i*d, ds->data+_clu.idx[i]*d, d);
}
// divide this cluster
assign = ivec_new(ni);
if(iclu == 30){
int _a = 1;
_a++;
ivec_print(_clu.idx, _clu.npts);
}
qerror = kmeans( d, ni, bfi, CLUSTERING_NITER, mem_points,
CLUSTERING_NTHREAD | KMEANS_QUIET | KMEANS_INIT_BERKELEY, CLUSTERING_SEED, CLUSTERING_NREDO,
cent, NULL, assign, nassign);
// prepare space for members' ids
for(i = 0; i < bfi; i++){
DyArray_init(&member[i], sizeof(int), nassign[i]);
}
// extract member points' ids for each children cluster
for(i = 0; i < ni; i++){
ori_id = _clu.idx[i];
DyArray_add(&member[assign[i]], (void*)&ori_id, 1);
}
// fulfill the type, centroids and the children of this cluster, add them to the ahct
_clu.type = ClusterType_Inner;
_clu.cents = fvec_new(d * bfi);
memcpy(_clu.cents, cent, sizeof(float)*d*bfi);
DyArray_init(&_clu.children, sizeof(int), bfi);
for(i = 0; i < bfi; i++){
Cluster_init(&clu, nassign[i]);
memcpy(clu.idx, (int*)member[i].elem, sizeof(int)*nassign[i]);
DyArray_add(&_clu.children, (void*)&ahct->count, 1); /* the i-th child's position */
DyArray_add(ahct, (void*)&clu, 1); /* add the i-th child to the ahct */
}
/* as per the elems of ahct may change when expanding the space
* we decide to get the brand new address of the element
*/
pclu = (Cluster*)DyArray_get(ahct, iclu, 1);
memcpy(pclu, &_clu, sizeof(Cluster));
/* report */
ivec_print(nassign, bfi);
ivec_print((int*)_clu.children.elem, _clu.children.count);
/* unset or release */
FREE(mem_points);
FREE(assign);
for(i = 0; i < bfi; i++){
DyArray_unset(&member[i]);
}
}
// move to next cluster
iclu++;
}
FREE(nassign);
FREE(cent);
FREE(member);
pclu = NULL;
}
int m, float alpha, float *R,
int nk, DoubleIndex **knnset, Cost *cost, int lb_type);
(Clustering *c, fDataSet *queryset, int m, float alpha, float *R, float *r_centroid, char *folder, int nk, DoubleIndex **knnset, Cost *cost)
{
char filename[256];
int nq = queryset->n,
qi, i, set_i;
int cid, point_num;
float knn_R;
float *set;
int *set_id;
int set_num;
float *set_vector = NULL;
float *query = fvec_new(d);
DoubleIndex candidate;
DoubleIndex *lowerbound = (DoubleIndex*)malloc(sizeof(DoubleIndex)*c->ncenter);
// lower bounds between query and all centers
Cost costi;
struct timeval tvb, tve, tvb_lb, tve_lb, tvb_io, tve_io;
for(qi = 0; qi < nq; qi++)
{
/// initialize the cost recorder
CostInit(&costi);
gettimeofday(&tvb, NULL);
/// the qi-th query
memcpy(query, queryset->data+qi*d, sizeof(float)*d);
knnset[qi] = (DoubleIndex*)malloc(sizeof(DoubleIndex)*nk);
/// calculate the lower bounds between query and all clusters to get the right order
/* n1 = pts */
static void nn_single_full (int distance_type,
int n1, int n2, int d,
const float *mat2, const float *mat1,
const float *vw_weights,
int *vw, float *vwdis)
{
int step1 = MIN (n1, BLOCK_N1), step2 = MIN (n2, BLOCK_N2);
float *dists = fvec_new (step1 * step2);
/* divide the dataset into sub-blocks to:
* - not make a too big dists2 output array
*/
long i1,i2,j1,j2;
for (i1 = 0; i1 < n1; i1 += step1) {
int m1 = MIN (step1, n1 - i1);
/* clear mins */
for (j1 = 0; j1 < m1; j1++) {
vw[j1+i1]=-1;
vwdis[j1+i1]=1e30;
}
for (i2 = 0; i2 < n2 ; i2 += step2) {
int m2 = MIN (step2, n2 - i2);
if(distance_type==2)
compute_cross_distances (d, m2, m1, mat2+i2*d, mat1+i1*d, dists);
else
compute_cross_distances_alt (distance_type, d, m2, m1, mat2+i2*d, mat1+i1*d, dists);
if(vw_weights) {
for(j1=0;j1<m1;j1++) for (j2 = 0; j2 < m2; j2++)
dists[j1 * m2 + j2] *= vw_weights[j2 + i2];
}
/* update mins */
for(j1=0;j1<m1;j1++) {
float *dline=dists+j1*m2;
int imin=vw[i1+j1];
float dmin=vwdis[i1+j1];
for(j2=0;j2<m2;j2++)
if(dline[j2]<dmin) {
imin=j2+i2;
dmin=dline[j2];
}
vw[i1+j1]=imin;
vwdis[i1+j1]=dmin;
}
}
}
free (dists);
}
void knn_full (int distance_type,int n1, int n2, int d, int k,
const float *mat2, const float *mat1,
const float *vw_weights,
int *vw, float *vwdis)
{
assert (k <= n2);
if(k==1) {
nn_single_full(distance_type, n1, n2, d, mat2, mat1, vw_weights, vw, vwdis);
return;
}
int step1 = MIN (n1, BLOCK_N1), step2 = MIN (n2, BLOCK_N2);
float *dists = fvec_new (step1 * step2);
/* allocate all heaps at once */
long oneh = fbinheap_sizeof(k);
// oneh=(oneh+7) & ~7; /* round up to 8 bytes */
char *minbuf = malloc (oneh * step1);
#define MINS(i) ((fbinheap_t*)(minbuf + oneh * i))
long i1,i2,j1,j2;
for (i1 = 0; i1 < n1; i1 += step1) {
int m1 = MIN (step1, n1 - i1);
/* clear mins */
for (j1 = 0; j1 < m1; j1++)
fbinheap_init(MINS(j1),k);
for (i2 = 0; i2 < n2 ; i2 += step2) {
int m2 = MIN (step2, n2 - i2);
if(distance_type==2)
compute_cross_distances (d, m2, m1, mat2+i2*d, mat1+i1*d, dists);
else
compute_cross_distances_alt (distance_type, d, m2, m1, mat2+i2*d, mat1+i1*d, dists);
if(vw_weights) {
for(j1=0;j1<m1;j1++) for (j2 = 0; j2 < m2; j2++)
dists[j1 * m2 + j2] *= vw_weights[j2 + i2];
}
/* update mins */
for(j1=0;j1<m1;j1++) {
float *dline=dists+j1*m2;
fbinheap_addn_label_range(MINS(j1),m2,i2,dline);
}
}
for (j1 = 0; j1 < m1; j1++) {
fbinheap_t *mh = MINS(j1);
assert (mh->k == k);
fbinheap_sort(mh, vw + (i1+j1) * k, vwdis + (i1+j1) * k);
}
}
#undef MINS
free (minbuf);
free(dists);
}
void vlad_compute(int k, int d, const float *centroids, int n, const float *v,int flags, float *desc)
{
int i,j,l,n_quantile,i0,i1,ai,a,ma,ni;
int *perm ;
float un , diff;
float *tab,*u,*avg,*sum,*mom2,*dists;
int *hist,*assign;
if(flags<11 || flags>=13)
{
assign=ivec_new(n);
nn(n,k,d,centroids,v,assign,NULL,NULL);
if(flags==6 || flags==7)
{
n_quantile = flags==6 ? 3 : 1;
fvec_0(desc,k*d*n_quantile);
perm = ivec_new(n);
tab = fvec_new(n);
ivec_sort_index(assign,n,perm);
i0=0;
for(i=0;i<k;i++)
{
i1=i0;
while(i1<n && assign[perm[i1]]==i)
{
i1++;
}
if(i1==i0) continue;
for(j=0;j<d;j++)
{
for(l=i0;l<i1;l++)
{
tab[l-i0]=v[perm[l]*d+j];
}
ni=i1-i0;
fvec_sort(tab,ni);
for(l=0;l<n_quantile;l++)
{
desc[(i*d+j)*n_quantile+l]=(tab[(l*ni+ni/2)/n_quantile]-centroids[i*d+j])*ni;
}
}
i0=i1;
}
free(perm);
free(tab);
}
else if(flags==5)
{
fvec_0(desc,k*d);
for(i=0;i<n;i++)
{
for(j=0;j<d;j++)
{
desc[assign[i]*d+j]+=v[i*d+j];
}
}
}
else if(flags==8 || flags==9)
{
fvec_0(desc,k*d);
u = fvec_new(d);
for(i=0;i<n;i++)
{
fvec_cpy(u,v+i*d,d);
fvec_sub(u,centroids+assign[i]*d,d);
un=(float)sqrt(fvec_norm2sqr(u,d));
if(un==0) continue;
if(flags==8)
{
fvec_div_by(u,d,un);
} else if(flags==9)
{
fvec_div_by(u,d,sqrt(un));
}
fvec_add(desc+assign[i]*d,u,d);
}
free(u);
}
else if(flags==10)
{
fvec_0(desc,k*d);
for(i=0;i<n;i++)
{
for(j=0;j<d;j++)
{
desc[assign[i]*d+j]+=v[i*d+j];
}
}
for(i=0;i<k;i++)
{
fvec_normalize(desc+i*d,d,2.0);
}
}
else if(flags==13)
{
fvec_0(desc,k*d);
for(i=0;i<n;i++)
{
for(j=0;j<d;j++)
{
desc[assign[i]*d+j]+=(float)sqr(v[i*d+j]-centroids[assign[i]*d+j]);
}
}
}
else if(flags==14)
{
avg = fvec_new_0(k*d);
for(i=0;i<n;i++)
{
for(j=0;j<d;j++)
{
avg[assign[i]*d+j]+=v[i*d+j]-centroids[assign[i]*d+j];
}
}
hist=ivec_new_histogram(k,assign,n);
for(i=0;i<k;i++)
{
if(hist[i]>0)
{
for(j=0;j<d;j++)
{
avg[i*d+j]/=hist[i];
}
}
}
free(hist);
fvec_0(desc,k*d);
for(i=0;i<n;i++)
{
for(j=0;j<d;j++)
{
desc[assign[i]*d+j]+=(float)(sqr(v[i*d+j]-centroids[assign[i]*d+j]-avg[assign[i]*d+j]));
}
}
fvec_sqrt(desc,k*d);
free(avg);
}
else if(flags==15)
{
fvec_0(desc,k*d*2);
sum = desc;
for(i=0;i<n;i++)
{
for(j=0;j<d;j++)
{
sum[assign[i]*d+j]+=v[i*d+j]-centroids[assign[i]*d+j];
}
}
hist = ivec_new_histogram(k,assign,n);
mom2 = desc+k*d;
for(i=0;i<n;i++)
{
ai=assign[i];
for(j=0;j<d;j++)
{
mom2[ai*d+j]+=(float)(sqr(v[i*d+j]-centroids[ai*d+j]-sum[ai*d+j]/hist[ai]));
}
}
fvec_sqrt(mom2,k*d);
free(hist);
}
else if(flags==17)
{
fvec_0(desc,k*d*2);
for(i=0;i<n;i++)
{
for(j=0;j<d;j++)
{
diff=v[i*d+j]-centroids[assign[i]*d+j];
if(diff>0)
{
desc[assign[i]*d+j]+=diff;
}
else
{
desc[assign[i]*d+j+k*d]-=diff;
}
}
}
}
else
{
fvec_0(desc,k*d);
for(i=0;i<n;i++)
{
for(j=0;j<d;j++)
{
desc[assign[i]*d+j]+=v[i*d+j]-centroids[assign[i]*d+j];
}
}
if(flags==1)
{
hist=ivec_new_histogram(k,assign,n);
/* printf("unbalance factor=%g\n",ivec_unbalanced_factor(hist,k)); */
for(i=0;i<k;i++)
{
for(j=0;j<d;j++)
{
desc[i*d+j]/=hist[i];
}
}
free(hist);
}
if(flags==2)
{
for(i=0;i<k;i++)
{
fvec_normalize(desc+i*d,d,2.0);
}
}
if(flags==3 || flags==4)
{
assert(!"not implemented");
}
if(flags==16)
{
hist=ivec_new_histogram(k,assign,n);
for(i=0;i<k;i++)
{
if(hist[i]>0)
{
fvec_norm(desc+i*d,d,2);
fvec_mul_by(desc+i*d,d,sqrt(hist[i]));
}
}
free(hist);
}
}
free(assign);
}
else if(flags==11 || flags==12)
{
ma=flags==11 ? 4 : 2;
assign=ivec_new(n*ma);
dists=knn(n,k,d,ma,centroids,v,assign,NULL,NULL);
fvec_0(desc,k*d);
for(i=0;i<n;i++)
{
for(j=0;j<d;j++)
{
for(a=0;a<ma;a++)
{
desc[assign[ma*i+a]*d+j]+=v[i*d+j]-centroids[assign[ma*i+a]*d+j];
}
}
}
free(dists);
free(assign);
}
}
int main()
{
int i, j, k, d = 10,d2=5;
float * a = fvec_new (d * d);
float * b = fvec_new (d * d);
float * b0 = fvec_new (d * d);
#define B0(i,j) b0[(i)+(j)*d]
#define A(i,j) a[(i)+(j)*d]
#define B(i,j) b[(i)+(j)*d]
float * lambda = fvec_new (d);
float * v = fvec_new (d * d);
float *v_part=fvec_new (d * d2);
for (i = 0 ; i < d ; i++)
for (j = 0 ; j <= i ; j++) {
A(i,j) = A(j,i) = drand48();
B0(i,j)=drand48();
B0(j,i)=drand48();
/* B(i,j) = B(j,i) = drand48(); */
}
/* make a positive definite b (with b=b0*b0') */
for (i = 0 ; i < d ; i++)
for (j = 0 ; j < d ; j++) {
double accu=0;
for(k=0;k<d;k++)
accu+=B0(i,k)*B0(j,k);
B(i,j)=accu;
}
printf ("a = ");
fmat_print(a,d,d);
printf ("\nb = ");
fmat_print(b,d,d);
printf ("Solution of the eigenproblem Av=lambda v\n");
printf ("\n");
int ret=eigs_sym (d, a, lambda, v);
assert(ret==0);
printf ("\n");
printf("Eigenvectors:\n");
fmat_print(v,d,d);
fprintf(stdout, "lambda = ");
fvec_print (lambda, d);
printf ("\n");
printf("Partial eigenvalues/vectors:\n");
printf ("\n");
ret=eigs_sym_part (d, a, d2, lambda, v_part);
assert(ret>0);
if(ret<d2)
printf("!!! only %d / %d eigenvalues converged\n",ret,d2);
printf ("\n");
printf("Eigenvectors:\n");
fmat_print(v_part,d,d2);
fprintf(stdout, "lambda = ");
fvec_print (lambda, d2);
printf ("\n");
printf ("Solution of the generalized eigenproblem Av=lambda B v\n");
printf ("\n");
ret=geigs_sym (d, a, b, lambda, v);
assert(ret==0);
printf ("\n");
fmat_print(v,d,d);
fprintf(stdout, "lambda = ");
fvec_print (lambda, d);
printf ("\n");
free (a);
free (lambda);
free (v);
return 0;
}
void gmm_fisher_spatial(int N, int K, int D,
const float *Q,
const float *sgmm,
const float *ll,
float *sdesc) {
float *Q_sum = fvec_new_0(K);
{
long k, n;
for(n = 0; n < N; n++)
for(k = 0; k < K; k++)
Q_sum[k] += Q[n * K + k];
for(k = 0; k < K; k++) Q_sum[k] /= N;
}
float *Q_ll, *Q_ll_2;
{
/* prepare a matrix containing both ll and ll**2 */
float *ll_ll2 = fvec_new(D * 2 * N);
fvec_cpy(ll_ll2, ll, D * N);
float *ll2 = ll_ll2 + D * N;
long i;
for(i = 0; i < D * N; i++)
ll2[i] = ll[i] * ll[i];
/* compute Q.T * ll_ll2 */
FINTEGER mi = K, ni = 2 * D, ki = N;
float one_over_N = 1.0 / N, zero = 0;
Q_ll = fvec_new(K * 2 * D);
Q_ll_2 = Q_ll + K * D;
sgemm_("N", "N", &mi, &ni, &ki,
&one_over_N, Q, &mi,
ll_ll2, &ki,
&zero, Q_ll, &mi);
free(ll_ll2);
}
{
const float *mm = sgmm;
float *d_mm = sdesc;
long k, d;
for(d = 0; d < D; d++)
for(k = 0; k < K; k++)
d_mm[d + k * D] = Q_ll[K * d + k] - Q_sum[k] * mm[d];
float *d_S = sdesc + K * D;
const float *S = sgmm + D;
for(d = 0; d < D; d++) {
float dfact = S[d] - mm[d] * mm[d];
for(k = 0; k < K; k++)
d_S[d + k * D] = -Q_ll_2[K * d + k] + 2 * Q_ll[K * d + k] * mm[d] + Q_sum[k] * dfact;
}
}
free(Q_ll);
free(Q_sum);
}
float *fmat_new (int nrow, int ncol)
{
float *m = fvec_new (nrow * (long)ncol);
return m;
}
void ANC::search(const fDataSet *baseset, const fDataSet *queryset, char *folder, int nk, DoubleIndex **knnset, Cost *cost, int lb_type)
{
char filename[256];
int nq = queryset->n,
qi, i, set_i;
int cid;
float knn_R;
float *set;
int *set_id;
int set_num;
float *set_vector = NULL;
float *query = fvec_new(d);
DoubleIndex candidate;
DoubleIndex *lb = (DoubleIndex*)malloc(sizeof(DoubleIndex)*ncenter);
// lower bounds between query and all centers
Cost costi;
struct timeval tvb, tve, tvb_lb, tve_lb, tvb_io, tve_io;
for(qi = 0; qi < nq; qi++)
{
/// initialize the cost recorder
CostInit(&costi);
gettimeofday(&tvb, NULL);
/// the qi-th query
memcpy(query, queryset->data+qi*d, sizeof(float)*d);
knnset[qi] = (DoubleIndex*)malloc(sizeof(DoubleIndex)*nk);
/// calculate and sort the lower bounds between query and all clusters to get the right order
gettimeofday(&tvb_lb, NULL);
if((int)Algorithm_Search_CrossLB == lb_type){
lowerbound_crosspoint(lb, query);
}else if((int)Algorithm_Search == lb_type){
lowerbound(lb, query, true);
}
gettimeofday(&tve_lb, NULL);
costi.lowerbound = timediff(tvb_lb, tve_lb);
/// search for knn
set_vector = fvec_new(d);
knn_R = FLOAT_MAX;
i = 0;
Heap heap(nk);
while(i < ncenter)
{
cid = lb[i].id;
// the i-th cluster
if(f_bigger(lb[i].val, knn_R))
{
break;
}
// knn_R > lb[i], means there are candidates in the i-th cluster
set_num = member[cid].size();
set = fvec_new(set_num*d);
set_id = ivec_new(set_num);
/* we do not test the time cost of disk page for speed, we do not really load the data
sprintf(filename, "%s/%d.cluster", folder, cid);
gettimeofday(&tvb_io, NULL);
HB_ClusterFromFile(filename, set_num, d, set, set_id);
gettimeofday(&tve_io, NULL);
costi.io = costi.io + timediff(tvb_io, tve_io);
*/
/* instead, we extract member points directly from the base set */
for(int mi = 0; mi < set_num; mi++){
int pts_id = member[cid][mi];
set_id[mi] = pts_id;
memcpy(set+mi*d, baseset->data+pts_id*d, sizeof(float)*d);
}
// update cost
costi.page = costi.page + 1;
costi.point = costi.point + set_num;
for(set_i = 0; set_i < set_num; set_i++)
{// calculate real distance between all candidates and query
candidate.id = set_id[set_i];
memcpy(set_vector, set+set_i*d, sizeof(float)*d);
candidate.val = odistance(query, set_vector, d);
if(heap.length < heap.MaxNum || f_bigger(heap.elem[0].val, candidate.val))
{// heap is not full or new value is smaller, insert
heap.max_insert(&candidate);
}
}
knn_R = heap.elem[0].val;
i++;
// free
free(set); set = NULL;
free(set_id); set_id = NULL;
}// end of search loop
// printf("%d ", i);//
memcpy(knnset[qi], heap.elem, sizeof(DoubleIndex)*heap.length);
gettimeofday(&tve, NULL);
costi.cpu = timediff(tvb, tve);
costi.search = costi.cpu - costi.lowerbound - costi.io;
/// sum new cost
CostCombine(cost, &costi);
}
CostMultiply(cost, 1/(float)nq);
free(set_vector); set_vector = NULL;
free(query); query = NULL;
free(lb); lb = NULL;
}
hkm_t *hkm_learn (int n, int d, int nlevel, int bf,
const float *points, int nb_iter_max, int nt, int verbose,
int **clust_assign_out)
{
int i, l, parent, k = 1;
hkm_t *hkm = hkm_new (d, nlevel, bf);
/* the absolute assignement of all points and the sizes of clusters */
int *node_assign = calloc (sizeof (int), n);
/* the buffer that receives the vectors gathered by parent node */
float *v = fvec_new (n * d);
/* Initialization */
for (l = 0; l < nlevel; l++) {
/* sort the vectors depending on which cluster they have been assigned to,
and compute the number of vectors assigned to each cluster
*** NOTE: to replace with the k_max function of ivfgeo
-> put this function in a separate library */
int *node_assign_idx = malloc (sizeof (*node_assign_idx) * n);
ivec_sort_index (node_assign, n, node_assign_idx);
/* Re-order the vectors depending on the previous order */
for (i = 0; i < n ; i++)
memmove (v + d * i, points + d * node_assign_idx[i],
sizeof (*points) * d);
/* k is the number of nodes/leaves at this level */
int pos = 0;
for (parent = 0; parent < k ; parent++) {
/* Count the number of vectors assigned to this internal node */
int nassign = 0;
while (pos + nassign < n)
if (node_assign[node_assign_idx[pos + nassign]] == parent)
nassign++;
else break;
if (verbose)
fprintf (stderr, "[Level %d | Parent %d] nassign=%d | pos=%d", l, parent, nassign, pos);
if (nassign == 0) {
fprintf (stderr, "# Problem2: no enough vectors in a node\n");
exit (1);
}
/* Perform the clustering on this subset of points */
int *clust_assign = ivec_new (nassign);
float * centroids = fvec_new (bf * d);
int nt = count_cpu();
int flags = nt | KMEANS_INIT_RANDOM | KMEANS_QUIET;
float err = kmeans (d, nassign, bf, nb_iter_max, v + d * pos, flags,
0, 1, centroids, NULL, clust_assign, NULL);
if (verbose)
fprintf (stderr, "-> err = %.3f\n", err);
memcpy (hkm->centroids[l] + d * parent * bf, centroids,
d * bf * sizeof (*centroids));
/* Update the indexes for those points */
for (i = 0; i < nassign; i++) {
int truepos = node_assign_idx[pos + i];
node_assign[truepos] = node_assign[truepos] * bf + clust_assign[i];
}
free (centroids);
free (clust_assign);
pos += nassign;
}
k *= bf;
free (node_assign_idx);
}
if(clust_assign_out) {
*clust_assign_out = (int *) malloc (n * sizeof (int));
memcpy (*clust_assign_out, node_assign, n * sizeof (int));
}
free (node_assign);
free (v);
return hkm;
}
void ANC::lowerbound_crosspoint(DoubleIndex *lb, const float *query){
int i, j, nci, otheri, ineighbor, id_n;
float max_dis, temp_dis, sdis_q_c, sdis_q_nc;
float *center = fvec_new(d);
float *ocenter = fvec_new(d);
DoubleIndex *sqdis_query_centroid; // square distance between query and all centroids
/// prepare the query centroid square distances
sqdis_query_centroid = (DoubleIndex*)malloc(sizeof(DoubleIndex)*ncenter);
for(nci = 0; nci < ncenter; nci++)
{
sqdis_query_centroid[nci].id = nci;
memcpy(center, centroid+nci*d, sizeof(float)*d);
sqdis_query_centroid[nci].val = odistance_square(query, center, d);
}
/// figure out lower bounds for each cluster
for(nci = 0; nci < ncenter; nci++){
int cnt = 0;
sdis_q_c = sqdis_query_centroid[nci].val; // square dis between (q and C)
memcpy(center, centroid+nci*d, sizeof(float)*d); // centroid of C
max_dis = FLOAT_ZERO;
for(i = 0; i < neighbor[nci].size(); i++){ // all neighbor clusters
id_n = neighbor[nci][i];
sdis_q_nc = sqdis_query_centroid[id_n].val; // square dis between (q and neighbor cluster)
if(f_bigger(sdis_q_c, sdis_q_nc)){ // separating hyperplane
cnt += 1;
memcpy(ocenter, centroid+id_n*d, sizeof(float)*d); // centroid of the neighbor cluster
temp_dis = crosspoint_distance(query, center, ocenter, d, sqrt(sdis_q_c));
if(f_bigger(temp_dis, max_dis))
{// a larger lower bound distance
max_dis = temp_dis;
}
}
}
lb[nci].id = nci;
lb[nci].val = max_dis;
}
/// sort lower bounds
DI_MergeSort(lb, 0, ncenter-1);
/// ### store into files
FILE *fp = open_file("lowerbound.txt", "w+");
for(i = 0; i < ncenter; i++){
fprintf(fp, " %d-%f", lb[i].id, lb[i].val);
}
fputc('\n', fp);
fclose(fp);
free(center); center = NULL;
free(ocenter); ocenter = NULL;
free(sqdis_query_centroid); sqdis_query_centroid = NULL;
}
void HBPlus::inner_lb_distance_OnePerPoint(const fDataSet *ds)
{
int i, j, nci, otheri;
float dis = 0;
float *xcenter = fvec_new(d);
float *ocenter = fvec_new(d);
float *x = fvec_new(d);
// distance between each centroid pair
float *centroid_dis_map = fvec_new_0(ncenter*ncenter);
innerLB = (DoubleIndex **)malloc(sizeof(DoubleIndex*)*ncenter);
for(i = 0; i < ncenter; i++){
innerLB[i] = NULL;
}
/// prepare distances between each two centroids
for(i = 0; i < ncenter; i++)
{
memcpy(xcenter, centroid+i*d, sizeof(float)*d);
for(j = 0; j <= i; j++)
{
memcpy(ocenter, centroid+j*d, sizeof(float)*d);
dis = odistance(xcenter, ocenter, d);
centroid_dis_map[i*ncenter+j] = dis;
if(i != j)
{
centroid_dis_map[j*ncenter+i] = dis;
}
}
}
// initialize the storing space for inner distance of each member point
for(nci = 0; nci < ncenter; nci++)
{
/// cnt_member_points
int cnt_member = member[nci].size();
innerLB[nci] = (DoubleIndex*)malloc(sizeof(DoubleIndex) * cnt_member);
for(i = 0; i < cnt_member; i++)
{
innerLB[nci][i].id = -1;
innerLB[nci][i].val = FLOAT_MAX;
}
}
for(nci = 0; nci < ncenter; nci++)
{
/* in each centroid */
memcpy(xcenter, centroid+nci*d, sizeof(float)*d); // the current centroid
int cnt_member = member[nci].size(); // cnt member points
/* for each member points */
for(i = 0; i < cnt_member; i++){
memcpy(x, ds->data+member[nci][i]*d, sizeof(float)*d);
/* for each other centroid */
for(otheri = 0; otheri < ncenter; otheri++)
{
if(otheri != nci)
{
memcpy(ocenter, centroid+otheri*d, sizeof(float)*d);
dis = (odistance_square(x, ocenter, d) - odistance_square(x, xcenter, d)) / (2*centroid_dis_map[nci*ncenter+otheri]);
if(f_bigger(innerLB[nci][i].val, dis))
{// update using smaller distance
innerLB[nci][i].val = dis;
innerLB[nci][i].id = member[nci][i]; // id is the data point
}
}
}
}
// sort member data points along the innerLB distance in the nci-th cluster
DI_MergeSort(innerLB[nci], 0, cnt_member-1);
}
free(centroid_dis_map); centroid_dis_map = NULL;
free(ocenter); ocenter = NULL;
free(xcenter); xcenter = NULL;
free(x); x = NULL;
}
/* estimate the GMM parameters */
static void gmm_compute_params (int n, const float * v, const float * p,
gmm_t * g,
int flags,
int n_thread)
{
long i, j;
long d=g->d, k=g->k;
float * vtmp = fvec_new (d);
float * mu_old = fvec_new_cpy (g->mu, k * d);
float * w_old = fvec_new_cpy (g->w, k);
fvec_0 (g->w, k);
fvec_0 (g->mu, k * d);
fvec_0 (g->sigma, k * d);
if(0) {
/* slow and simple */
for (j = 0 ; j < k ; j++) {
double dtmp = 0;
for (i = 0 ; i < n ; i++) {
/* contribution to the gaussian weight */
dtmp += p[i * k + j];
/* contribution to mu */
fvec_cpy (vtmp, v + i * d, d);
fvec_mul_by (vtmp, d, p[i * k + j]);
fvec_add (g->mu + j * d, vtmp, d);
/* contribution to the variance */
fvec_cpy (vtmp, v + i * d, d);
fvec_sub (vtmp, mu_old + j * d, d);
fvec_sqr (vtmp, d);
fvec_mul_by (vtmp, d, p[i * k + j]);
fvec_add (g->sigma + j * d, vtmp, d);
}
g->w[j] = dtmp;
}
} else {
/* fast and complicated */
if(n_thread<=1)
compute_sum_dcov(n,k,d,v,mu_old,p,g->mu,g->sigma,g->w);
else
compute_sum_dcov_thread(n,k,d,v,mu_old,p,g->mu,g->sigma,g->w,n_thread);
}
if(flags & GMM_FLAGS_1SIGMA) {
for (j = 0 ; j < k ; j++) {
float *sigma_j=g->sigma+j*d;
double var=fvec_sum(sigma_j,d)/d;
fvec_set(sigma_j,d,var);
}
}
long nz=0;
for(i=0; i<k*d; i++)
if(g->sigma[i]<min_sigma) {
g->sigma[i]=min_sigma;
nz++;
}
if(nz) printf("WARN %ld sigma diagonals are too small (set to %g)\n",nz,min_sigma);
for (j = 0 ; j < k ; j++) {
fvec_div_by (g->mu + j * d, d, g->w[j]);
fvec_div_by (g->sigma + j * d, d, g->w[j]);
}
assert(finite(fvec_sum(g->mu, k*d)));
fvec_normalize (g->w, k, 1);
printf ("w = ");
fvec_print (g->w, k);
double imfac = k * fvec_sum_sqr (g->w, k);
printf (" imfac = %.3f\n", imfac);
free (vtmp);
free (w_old);
free (mu_old);
}
float *fvec_new_nan (long n)
{
float *ret = fvec_new(n);
fvec_nan(ret,n);
return ret;
}
void gmm_compute_p (int n, const float * v,
const gmm_t * g,
float * p,
int flags)
{
if(n==0) return; /* sgemm doesn't like empty matrices */
long i, j, l;
double dtmp;
long d=g->d, k=g->k;
float * logdetnr = fvec_new(k);
for (j = 0 ; j < k ; j++) {
logdetnr[j] = -d / 2.0 * log (2 * M_PI);
for (i = 0 ; i < d ; i++)
logdetnr[j] -= 0.5 * log (g->sigma[j * d + i]);
}
/* compute all probabilities in log domain */
/* compute squared Mahalanobis distances (result in p) */
if(0) { /* simple & slow */
for (i = 0 ; i < n ; i++) {
for (j = 0 ; j < k ; j++) {
dtmp = 0;
for (l = 0 ; l < d ; l++) {
dtmp += sqr (v[i * d + l] - g->mu[j * d + l]) / g->sigma[j * d + l];
}
p[i * k + j] = dtmp;
}
}
} else { /* complicated & fast */
compute_mahalanobis_sqr(n,k,d,g->mu,g->sigma,v,p);
}
/* convert distances to probabilities, staying in the log domain
until the very end */
for (i = 0 ; i < n ; i++) {
for (j = 0 ; j < k ; j++) {
p[i * k + j] = logdetnr[j] - 0.5 * p[i * k + j];
CHECKFINITE(p[i * k + j]);
}
/* at this point, we have p(x|ci) -> we want p(ci|x) */
if(flags & GMM_FLAGS_NO_NORM) { /* compute the normalization factor */
dtmp=0;
} else {
dtmp = p[i * k + 0];
if(flags & GMM_FLAGS_W)
dtmp+=log(g->w[0]);
for (j = 1 ; j < k ; j++) {
double log_p=p[i * k + j];
if(flags & GMM_FLAGS_W)
log_p+=log(g->w[j]);
dtmp = log_sum (dtmp, log_p);
}
/* now dtmp contains the log of sums */
}
for (j = 0 ; j < k ; j++) {
double log_norm=0;
if(flags & GMM_FLAGS_W)
log_norm=log(g->w[j])-dtmp;
else
log_norm=-dtmp;
p[i * k + j] = exp (p[i * k + j] + log_norm);
CHECKFINITE(p[i * k + j]);
}
// printf ("p[%d] = ", i);
// fvec_print (p + i * k, k);
}
free(logdetnr);
}
float * fvec_new_randn_r (long n, unsigned int seed)
{
float * f = fvec_new (n);
fvec_randn_r(f,n,seed);
return f;
}
int merge_ordered_sets (const int **labels,const float **vals,
const int *sizes,int k,
int **labels_out,float **vals_out) {
int i,j;
int n_out = ivec_sum (sizes, k);
int *all_labels = ivec_new (n_out);
float *all_vals = fvec_new (n_out);
/* Maxheap:
* * maxheap label = index of table in 0..k-1
* * maxheap val = - (label from labels table)
*
* If maxheap val does not fit in a float (if label>2**24), it
* triggers an assertion. Time to implement a maxheap with int
* values...
*/
fbinheap_t *mh = fbinheap_new(k);
/* current index on table k */
int indices[k];
for ( i = 0 ; i < k ; i++) {
if (sizes[i] == 0)
continue;
indices[i] = 0;
int label = labels[i][0];
float mh_val = -label;
assert ((int)(-mh_val) == label || !"lost precision in int->float conversion");
fbinheap_add (mh, i, mh_val);
}
int all_i = 0;
while (mh->k>0) {
/* smallest available label */
i = mh->label[1]; /* index of table */
j = (int)(-mh->val[1]); /* label */
/* I don't dare compiling with -DNDEBUG */
/* assert(j==labels[i][indices[i]]); */
all_labels[all_i] = j;
all_vals[all_i] = vals[i][indices[i]];
all_i++;
/* remove handled label */
fbinheap_pop (mh);
indices[i]++;
if (indices[i] < sizes[i]) { /* push next label from this table */
int label = labels[i][indices[i]];
float mh_val = -label;
assert ((int)(-mh_val) == label || !"lost precision in int->float conversion");
fbinheap_add (mh, i, mh_val);
}
}
fbinheap_delete (mh);
assert (all_i == n_out);
*labels_out = all_labels;
*vals_out = all_vals;
return n_out;
}