fortperc
See documentation here. (Generated by the brilliant tool FORD.)
This library contains various useful functions for doing percolation in Fortran.
src/hk.f90 contains a Fortran implementation of the Hoshen-Kopelman algorithm, inspired by Tobin Fricke's C implementation at https://gist.github.com/tobin/909424.
src/percolation.f90 contains subroutines/functions which calculate common quantities in percolation, such as the size distribution of clusters, the density of the percolating cluster, etc.