#!/usr/bin/python
# -*- coding: utf8 -*-

import matplotlib.pyplot as plt
import matplotlib as mpl
import numpy as np
from math import *

code_website = 'https://commons.wikimedia.org/wiki/User:Geek3/mplwp'
try:
    import mplwp
except ImportError, er:
    print 'ImportError:', er
    print 'You need to download mplwp.py from', code_website
    exit(1)

name = 'Mplwp_Helmholtz_coil_field.svg'
fig = mplwp.fig_standard(mpl)
mplwp.set_bordersize(fig, 58.5, 16.5, 16.5, 44.5)
xlim = -2, 2; fig.gca().set_xlim(xlim)
ylim = 0,1.5; fig.gca().set_ylim(ylim)
mplwp.mark_axeszero(fig.gca())
plt.xlabel(ur'$z\,/\,R$')
plt.ylabel(ur'$B_z\ [\mu_0I\,/\,(2R)]$')

plt.plot([-0.5, 0.5], [1.1, 1.1], color='k', marker='