The program calculates the degree of sphericity by comparing the distribution of circular variances for the atoms in a moleule with the same distribution for a set of atoms inside a sphere [M. Mezei, J. Math. Chem., 53, 2184-2189 (2015); doi: 10.1007/s10910-015-0540-4].

The program is run with command line arguments:

cvdistr [options]

where the following options are available:

• -h : Print the list of options
• -cvrefgrid ngrid : calculate the sphere CV distribution on a cubic grid, ngrid grids each direction
• -cvrefran maxran : calculate the sphere CV distribution on a random grid, a total of maxran points
• -cvcomp file : Read the structure in PDB format from file
• -grids ngrids : use the cubic grid with ngrids points for comparison
• -ncvbins maxbin : use maxbin bins for the CV distribution
• -stretch gx gy gz : Compare the spherical grid with a grid stretched by <gx, gy, gz>
• -cvcomplist file : Read the list of pdb files from file and compare their CV distribution with the reference distribution
• -sfalist file : Read the sphericity records calculated with sfanal for correlation
• -momcorr exponent: calculate correlation for up to the moment exponent
• -plot file : write the distributions to file for gnuplot
• -debug : print debugging output

The program is written in Fortran-77 and can be compiled with any Fortran compiler, including GNU fortran:

f77 -o cvdistr cvdistr.f

to obtain the executable cvdistr