Pdf now is real with the negative values setted to 0
integrate the rt0p from the signal
integrate the rt0p from the propagator
integrate the MSD discrete verison
add the normalization for the b0 in the rt0p_signal
add some comments
add file test_dsi_metrics.py
code review of @maurozucchelli DSI metrics contributions. Need to find a way to test MSD
delete the normalization on rtop_signal and speed up its computation.py
add comments and calculate radius and diameter automatically
fixed a bug in MSD_discrete
fixed a bug in rtop_signal
delited the rtop_signal non norm
fix the code deleting the rtop_signal non norm
change MSD to msd
change MSD to msd
change MSD to msd
fixed bug in self.dn
modify rtop_signal
add test on MSD first try