import numpy

slices = 100.

bound = 8.

width = 2.*bound/slices

enot = 8.85*10**-12

rho = (1.5*10**-7)/(8*bound**3)

x = numpy.arange(0,2*bound, width)
y = numpy.arange(0,2*bound, width)
z = numpy.arange(0,2*bound, width)

field = [[x],[y],[z]]

xx = numpy.zeros(x.size)
yy = numpy.zeros(y.size)
zz = numpy.zeros(z.size)

for i in range(0,x.size):
    xx[i] = -bound + i*width
    yy[i] = -bound + i*width
    zz[i] = -bound + i*width

v = numpy.array([xx,yy,zz])


change = 1.
while change < 2:
    for i in range(1, xx.size-1):
            print i
            v[i][i][i] = v[i+1][i][i]+v[i-1][i][i]
    for j in range(1, xx.size-1):
            v[j][j][j] = v[j][j+1][j]+v[j][j-1][j]
    for k in range(1, xx.size-1):
            v[k][k][k] = v[k][k][k+1]+v[k][k][k-1]
    v = (1./6)*v + (width**2/6*enot)*rho
    change = change + 1