Added Pareto and Weibull distributions, courtesy Jeremy Hylton.
diff --git a/Lib/random.py b/Lib/random.py
index 608203f..52a4266 100644
--- a/Lib/random.py
+++ b/Lib/random.py
@@ -212,6 +212,22 @@
z = expovariate(1.0/beta)
return z/(y+z)
+# -------------------- pareto --------------------
+
+def paretovariate(alpha):
+ # Jain, pg. 495
+
+ u = random()
+ return 1.0 / pow(u, 1.0/alpha)
+
+# -------------------- pareto --------------------
+
+def weibullvariate(alpha, beta):
+ # Jain, pg. 499; bug fix courtesy Bill Arms
+
+ u = random()
+ return alpha * pow(-log(u), 1.0/beta)
+
# -------------------- test program --------------------
def test(N = 200):
@@ -233,6 +249,8 @@
test_generator(N, 'gammavariate(200.0, 1.0)')
test_generator(N, 'gauss(0.0, 1.0)')
test_generator(N, 'betavariate(3.0, 3.0)')
+ test_generator(N, 'paretovariate(1.0)')
+ test_generator(N, 'weibullvariate(1.0, 1.0)')
def test_generator(n, funccall):
import time