creating a non uniform distribution of points in 3D

creating a non uniform distribution of points in 3D

I am trying to have a non-uniform and uniform distribution of points in
3D. Is there any way I can do so automatically? Do I use some sort of
meshing software. I want it return a file stating the positions of the
various points. Can some one help me out? And I also want this procedure
to me repeatable for various number of points that I need. I want to start
off with 100 then 200 , 300 etc..