Reference: Chapter 8 of Scattering of Electromagnetic Waves: Numerical Simulations
mcpdf.m generate random realizations of positions for hard spheres using the Monte Carlo method (also known as Metropolis shuffling). The pair distribution is computed by counting number of occurrences of pair separations.
The figure below is generated with the following parameters (The PY results is generated using pypdf.m.)
ntot=200, fv=0.3, cnst=0.35, npsr=100, nrlz=30, seed=54321