E/M Homework

import numpy

e0 = 8.85*10**-12 #C^2/Nm^2

x = 5. #meters
y = 5. #meters
z = 8. #meters

width = 0.001

dx = numpy.arange(-1,1,width)

intx = numpy.zeros(dx.size)
inty = numpy.zeros(dx.size)
intz = numpy.zeros(dx.size)

#Calculating Electric Field
for i in range(dx.size):
    lamb = (6.0*10**-6)*(1-dx[i]**2)
    intx[i] = width*(1./(4.*numpy.pi*e0))*lamb*(x-dx[i])/(((x-dx[i])**2 + y**2 + z**2)**(3./2))
    inty[i] = width*(1./(4.*numpy.pi*e0))*lamb*(y)/(((x-dx[i])**2 + y**2 + z**2)**(3./2))
    intz[i] = width*(1./(4.*numpy.pi*e0))*lamb*(z)/(((x-dx[i])**2 + y**2 + z**2)**(3./2))

x_sum = numpy.sum(intx)
y_sum = numpy.sum(inty)
z_sum = numpy.sum(intz)

potx = numpy.zeros(dx.size)

#Calculating Electrostatic Potential
for i in range(dx.size):
    lamb = (6.0*10**-6)*(1-dx[i]**2)
    potx[i] = width*(1./(4.*numpy.pi*e0))*lamb/(((x-dx[i])**2 + y**2 + z**2)**(1./2))

potsum = numpy.sum(potx)

potplus = numpy.zeros(dx.size)
potminus = numpy.zeros(dx.size)
dv = 0.001

#Calculating Electrostatic Potential at small points
for i in range(dx.size):
    lamb = (6.0*10**-6)*(1-dx[i]**2)
    potplus[i] = width*(1./(4.*numpy.pi*e0))*lamb/((((x+dv)-dx[i])**2 + y**2 + z**2)**(1./2))
    potminus[i] = width*(1./(4.*numpy.pi*e0))*lamb/((((x-dv)-dx[i])**2 + y**2 + z**2)**(1./2))

Etest = -(numpy.sum(potplus) - numpy.sum(potminus))/(2*dv)

Error = 100*numpy.abs(x_sum-Etest)/Etest

print ('Coordinates of E field are '),x_sum,(' x^ ,'),y_sum,(' y^ ,'),z_sum,(' z^')
print ('Electrostatic potential is '),potsum
print ('Approximation of Electric Field at X is '),Etest
print ('Percent error between approximation and actual is '),Error,('%')