for (int i=0; i<_nb_distant_points; i++)
for (int j=0; j <nbcomp; j++)
distant_values[i*nbcomp+j]=values[(_distant_locations[i]-1)*nbcomp+j];
for (int i=0; i<_nb_distant_points; i++)
for (int j=0; j <nbcomp; j++)
distant_values[i*nbcomp+j]=values[(_distant_locations[i]-1)*nbcomp+j];