binomial plot with unicode labels

binomplot.py

%matplotlib inline
import matplotlib.pyplot as plt
from matplotlib import rc

# To use unicode, turn off latex 
#rc('text', usetex=True)

import math
import numpy as np
import scipy as sp
import scipy.stats
from scipy.stats import binom
import pandas as pd
from IPython.html.widgets import interact, interactive, fixed
from IPython.html import widgets
from IPython.display import clear_output, display, HTML

def binomialHiLite(n, p, alpha):
    ''' 
       plots probability histogram for a binomial with parameters n and p, 
       highlighting the upper alpha quantile in yelow.
       Red vertical line plotted at the mean.
    '''
    fig, ax = plt.subplots(nrows=1, ncols=1)
    x = np.arange(n+1)
    val = binom.ppf(1-alpha, n, p)
    inx = np.searchsorted(x, val, side="right")
    xb = x[:inx]
    xy = x[inx:]
    width = 1.0
    ax.bar(xb, binom.pmf(xb, n, p), width, color='b', align='center')
    hilit = ax.bar(xy, binom.pmf(xy, n, p), width, color='y', align='center')
    plt.xlim([-width,n+width])
    plt.axvline(x=n*p, color='r')
    probStr = str(round(100*(1-binom.cdf(x[inx-1],n, p)),2))
    #label = r'$\mathbf{P}(X \ge' + str(x[inx]) + r') \approx' + probStr + '$'
    label = u'P(X \u2265 %s) \u2248 %s' % (x[inx], probStr)
    plt.legend([hilit[0]],
               [label],
               loc = 'best')

interact(binomialHiLite, n=widgets.IntSliderWidget(min=5, max=300, step=5, value=30),\
         p=widgets.FloatSliderWidget(min=0.001, max=1, step=0.001, value=.5),\
         alpha=widgets.FloatSliderWidget(min=0.0, max=1.0, step=0.001, value=.05)
        );