#!/usr/bin/env python3
from random import random
def check_cond_prob(side, seq):
total = 0 # total num of cases where this side exists and we can condition by it
conditioned = 0 # got same side after just seeing it
last_letter = seq[0]
for letter in seq[1:]:
if last_letter == side:
total += 1
if last_letter == side and letter == side:
conditioned += 1
last_letter = letter
print('saw AND got: ' + str(conditioned), 'total: ' + str(total))
return conditioned/total
def generate_ran_seq():
seq = ''
for _ in range(300):
if random() <= 0.5:
seq += 'H'
else:
seq += 'T'
return seq
def main():
# read in sequences from files into strings
seq1 = ''.join([letter for letter in open('ditherSequence1.txt')])
seq2 = ''.join([letter for letter in open('ditherSequence2.txt')])
print('sequence 1')
print(seq1)
print('P(got heads | saw heads): ' + str(check_cond_prob('H', seq1)))
print('P(got tails | saw tails): ' + str(check_cond_prob('T', seq1)))
print()
print('sequence 2')
print(seq2)
print('P(got heads | saw heads): ' + str(check_cond_prob('H', seq2)))
print('P(got tails | saw tails): ' + str(check_cond_prob('T', seq2)))
print()
print('Truly random sequence')
r = generate_ran_seq()
print(r)
print('P(got heads | saw heads): ' + str(check_cond_prob('H', r)))
print('P(got heads | saw heads): ' + str(check_cond_prob('T', r)))
if __name__ == "__main__":
main()
