Dice probabilities

[Dave Britten]

Here's a short Python program I wrote a long time ago for generating probability tables:

https://gist.github.com/dave-britten/c4b...65ce54497b

Roughly half of it is just processing the user input! Enter one die at a time, and enter a blank line to terminate input.

EDIT: It's so old, in fact, that I just realized it's for Python 2! Here's a quick update to Python 3:

Code:

import re

dice = [] #Input dice as polynomial coefficients    

print("Enter face values as non-negative integers, separated by spaces, commas, or semicolons. (e.g. \"1,2;3 4 5 6\")")
while True:
    rawdie = [] #List of face values
    qty = 1 #Quantity of a single die spec

    inp = input("Die " + str(len(dice) + 1) + "? ")
    if inp == "":
        break
    #rawdie = [int(face) for face in inp.split(" ")]
    rawdie = [int(face.strip()) for face in re.split(" |,|;", inp) if face.strip()]
    qty = input("Quantity? [1] ")

    if qty == "":
        qty = 1
    else:
        qty = int(qty)

    die = [0] * (max(rawdie) + 1)
    for i in rawdie:
        die[i] += 1

    dice += [die for i in range(qty)]

    print(str(rawdie) + " x " + str(qty))

lastresult = dice[0]

for current in dice[1:]:
    result = [0] * (len(lastresult) + len(current) - 1)
    for x, v1 in enumerate(lastresult):
        if v1 == 0:
            continue
        for y, v2 in enumerate(current):
            result[x + y] += v1 * v2
    lastresult = result

skipzero = True
p = 0.0
fcum = 0.0
for i in lastresult:
    p += i

print("Permutations: {:.0f}".format(p))
print("{:<6} {:<12} {:>10} {:>10} {:>10}".format("Total","Freq","Prob", "p>=", "p<="))
for i, f in enumerate(lastresult):
    fcum += f
    if f == 0 and skipzero:
        continue
    skipzero = False
    print("{:<6} {:<12} {:>10.3%} {:>10.3%} {:>10.3%}".format(i, f, f / p, (p - fcum + f) / p, fcum / p))