summaryrefslogtreecommitdiff
path: root/Lib/test/test_random.py
diff options
context:
space:
mode:
authorRaymond Hettinger <python@rcn.com>2016-10-29 17:42:36 -0700
committerRaymond Hettinger <python@rcn.com>2016-10-29 17:42:36 -0700
commit77d574d4aeae4b7b9b976a68b367783a0932b6c8 (patch)
tree049ed86c42e205a2f0dcca11f6344e929b0a184e /Lib/test/test_random.py
parent30d00e54dde47b11f5b338aaba17760b641e1705 (diff)
downloadcpython-git-77d574d4aeae4b7b9b976a68b367783a0932b6c8.tar.gz
Issue #18844: Strengthen tests to include a case with unequal weighting
Diffstat (limited to 'Lib/test/test_random.py')
-rw-r--r--Lib/test/test_random.py17
1 files changed, 17 insertions, 0 deletions
diff --git a/Lib/test/test_random.py b/Lib/test/test_random.py
index dd2715288a..a4413b5146 100644
--- a/Lib/test/test_random.py
+++ b/Lib/test/test_random.py
@@ -645,6 +645,23 @@ class MersenneTwister_TestBasicOps(TestBasicOps, unittest.TestCase):
c = self.gen.choices(range(n), cum_weights=range(1, n+1), k=10000)
self.assertEqual(a, c)
+ # Amerian Roulette
+ population = ['Red', 'Black', 'Green']
+ weights = [18, 18, 2]
+ cum_weights = [18, 36, 38]
+ expanded_population = ['Red'] * 18 + ['Black'] * 18 + ['Green'] * 2
+
+ self.gen.seed(9035768)
+ a = self.gen.choices(expanded_population, k=10000)
+
+ self.gen.seed(9035768)
+ b = self.gen.choices(population, weights, k=10000)
+ self.assertEqual(a, b)
+
+ self.gen.seed(9035768)
+ c = self.gen.choices(population, cum_weights=cum_weights, k=10000)
+ self.assertEqual(a, c)
+
def gamma(z, sqrt2pi=(2.0*pi)**0.5):
# Reflection to right half of complex plane
if z < 0.5: