integrates density from a cube file (usually not a good idea!)

cube_el.py

#!/usr/bin/env python
import sys
import numpy as np

cubefile = sys.argv[1]

f = open(cubefile, 'r')
line = f.next()
line = f.next()
line = f.next()
numatoms = int(line.strip().split()[0])

# volume vectors
axvec = []
for i in range(3):
    line = f.next()
    gdpts = int(line.strip().split()[0])
    vec = [float(xyz) for xyz in line.strip().split()[1:]]
    axvec.append(vec[i])

for i in range(numatoms):
    f.next()

electrons = 0
dV = axvec[0]*axvec[1]*axvec[2]

for line in f:
    edens = [float(val) for val in line.strip().split()]
    for thisdens in edens:
        electrons += thisdens*dV

print electrons

f.close()