dice is the key | Python Fiddle

import pylab
import random

def simdices():
    values = [1,2,3,4,5,6, 7,8,9,10]
    results = { 1:0 , 2:0 , 3:0 , 4:0 , 5:0 , 6:0, 7:0, 8:0, 9:0, 10:0 }
    results2 = { 1:0 , 2:0 , 3:0 , 4:0 , 5:0 , 6:0, 7:0, 8:0, 9:0, 10:0 }       
    resultsCombined = { 1:0 , 2:0 , 3:0 , 4:0 , 5:0 , 6:0, 7:0, 8:0, 9:0, 10:0, 11:0, 12:0, 13:0, 14:0, 15:0, 16:0, 17:0, 18:0, 19:0, 20:0 }
    for i in range(1000000):
        value1 = random.choice(values)
        value2 = random.choice(values)
        results[value1] +=1
        results2[value2] +=1
        resultsCombined[value1+value2] +=1
    print results.values()
    bins = [1,2,3,4,5,6, 7,8,9,10,11,12,13,14,15,16,17,18,19,20]
    #y = results.values()
    #pylab.hist(results.values(), histtype='bar', color='r', stacked=True, align = 'mid', alpha=0.5, label='Vowels proportion')
    pylab.bar(values, results.values(),  align='center', color='r', alpha=0.2, label='Count of results')
    pylab.bar(values, results2.values(),  align='center', color='b', alpha=0.5, label='Count of results 2')
    pylab.bar(bins, resultsCombined.values(),  align='center', color='g', alpha=0.5, label='Count of results combined')
    pylab.title("Results for 1 million rolling of a die with 10 faces")
    pylab.xlim([1,20])
    pylab.xlabel("Face result")
    pylab.ylabel("Frequency")    
    pylab.xticks(bins)
    #pylab.fill_between(x, y1, y2, where=y2>=y1, facecolor='green', interpolate=True)
    pylab.grid(True)
    pylab.legend()
    #pylab.savefig('L15_P5_graph.png')
    pylab.show()

simdices()

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