[src] added new file : it enables to compute the pdf on a 3D grid using multprocessing. Evaluation on grid of 128^3 elements is less than 2 mn using 8 cpu
[src] updated parallel computations of PDF on 3D grids: added more debug messages, added missing docstring, , uses of python logging instead of ot one. renamed functions to be more coherant
[src] minor cosmetics on parallel_pdf computations. Added also missing pool.close. Ongoing work
[src] fixed minor bugs and warnings
[src] added new function to compute the characteristic function basing on mp.pool
Do not parallelize 1D and 2D contributions into 3D, time is negligible

Set chunksize to N*N.
Remove pool.terminate() and pool.close() to avoid pool overhead; explicitly
delete dcf array to avoid memory exhaustion.