Minor touch-ups to the random module examples

This commit is contained in:
Raymond Hettinger 2016-11-16 21:34:17 -08:00
parent be1ed8b028
commit 2589ee3e2b
1 changed files with 6 additions and 5 deletions

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@ -344,15 +344,15 @@ Basic usage::
>>> deck >>> deck
['king', 'queen', 'ace', 'jack'] ['king', 'queen', 'ace', 'jack']
>>> random.sample([1, 2, 3, 4, 5], 3) # Three samples without replacement >>> random.sample([1, 2, 3, 4, 5], k=3) # Three samples without replacement
[4, 1, 5] [4, 1, 5]
>>> # Six weighted samples with replacement >>> # Six weighted samples with replacement
>>> choices(['red', 'black', 'green'], [18, 18, 2], k=6) >>> choices(['red', 'black', 'green'], [18, 18, 2], k=6)
['red', 'green', 'black', 'black', 'red', 'black'] ['red', 'green', 'black', 'black', 'red', 'black']
# Probability of getting 5 or more heads from 7 spins of a biased coin # Probability of getting 5 or more heads from 7 spins
# that settles on heads 60% of the time. # of a biased coin that settles on heads 60% of the time.
>>> n = 10000 >>> n = 10000
>>> cw = [0.60, 1.00] >>> cw = [0.60, 1.00]
>>> sum(choices('HT', cum_weights=cw, k=7).count('H') >= 5 for i in range(n)) / n >>> sum(choices('HT', cum_weights=cw, k=7).count('H') >= 5 for i in range(n)) / n
@ -369,5 +369,6 @@ sample of size five::
data = 1, 2, 4, 4, 10 data = 1, 2, 4, 4, 10
means = sorted(mean(choices(data, k=5)) for i in range(20)) means = sorted(mean(choices(data, k=5)) for i in range(20))
print('The sample mean of {:.1f} has a 90% confidence interval ' print(f'The sample mean of {mean(data):.1f} has a 90% confidence '
'from {:.1f} to {:.1f}'.format(mean(data), means[1], means[-2])) f'interval from {means[1]:.1f} to {means[-2]:.1f}')