pca->n= n;
pca->z = av_malloc_array(n, sizeof(*pca->z));
pca->count=0;
pca->covariance= av_calloc(n*n, sizeof(double));
pca->mean= av_calloc(n, sizeof(double));
pca->n= n;
pca->z = av_malloc_array(n, sizeof(*pca->z));
pca->count=0;
pca->covariance= av_calloc(n*n, sizeof(double));
pca->mean= av_calloc(n, sizeof(double));