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

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

code_website = 'http://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_polylogarithm_m3to3.svg'
fig = mplwp.fig_standard(mpl)

xlim = -3.75,1.25; fig.gca().set_xlim(xlim)
ylim = -2.25,2.25; fig.gca().set_ylim(ylim)
mplwp.mark_axeszero(fig.gca())

import mpmath

for s in range(-3, 3+1):
    if s > 1:
        x = np.linspace(xlim[0], 1, 5001)
    else:
        x = np.linspace(xlim[0], 1, 5001)[:-1]
    y = [float(mpmath.polylog(s, xx).real) for xx in x]
    plt.plot(x, y, label='Li' + mplwp.unicode_sub(s))

plt.legend(loc='upper center', ncol=2).get_frame().set_alpha(0.9)

plt.savefig(name)
mplwp.postprocess(name)