Issue 13355: Make random.triangular degrade gracefully when low == high.
diff --git a/Lib/random.py b/Lib/random.py
index 174e755..4642928 100644
--- a/Lib/random.py
+++ b/Lib/random.py
@@ -355,7 +355,10 @@
"""
u = self.random()
- c = 0.5 if mode is None else (mode - low) / (high - low)
+ try:
+ c = 0.5 if mode is None else (mode - low) / (high - low)
+ except ZeroDivisionError:
+ return low
if u > c:
u = 1.0 - u
c = 1.0 - c
diff --git a/Lib/test/test_random.py b/Lib/test/test_random.py
index 37a222d..103d462 100644
--- a/Lib/test/test_random.py
+++ b/Lib/test/test_random.py
@@ -602,7 +602,7 @@
for variate, args, expected in [
(g.uniform, (10.0, 10.0), 10.0),
(g.triangular, (10.0, 10.0), 10.0),
- #(g.triangular, (10.0, 10.0, 10.0), 10.0),
+ (g.triangular, (10.0, 10.0, 10.0), 10.0),
(g.expovariate, (float('inf'),), 0.0),
(g.vonmisesvariate, (3.0, float('inf')), 3.0),
(g.gauss, (10.0, 0.0), 10.0),
diff --git a/Misc/NEWS b/Misc/NEWS
index 05230da..950040b 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -24,6 +24,9 @@
- Issue #14710: pkgutil.find_loader() no longer raises an exception when a
module doesn't exist.
+- Issue #13355: random.triangular() no longer fails with a ZeroDivisionError
+ when low equals high.
+
- Issue #21538: The plistlib module now supports loading of binary plist files
when reference or offset size is not a power of two.