From: Brad Fitzpatrick <bradfitz@golang.org>
Date: Sun, 28 Apr 2013 01:50:38 +0000 (-0700)
Subject: math/rand: fix typo and add better crash message
X-Git-Tag: go1.1rc2~42
X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=e9546a01dcb4678476157c3bcdcf8c02a0688f54;p=gostls13.git

math/rand: fix typo and add better crash message

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/9000043
---

diff --git a/src/pkg/math/rand/zipf.go b/src/pkg/math/rand/zipf.go
index 38e8ec5162..8db2c6f5bf 100644
--- a/src/pkg/math/rand/zipf.go
+++ b/src/pkg/math/rand/zipf.go
@@ -34,7 +34,6 @@ func (z *Zipf) hinv(x float64) float64 {
 
 // NewZipf returns a Zipf generating variates p(k) on [0, imax]
 // proportional to (v+k)**(-s) where s>1 and k>=0, and v>=1.
-//
 func NewZipf(r *Rand, s float64, v float64, imax uint64) *Zipf {
 	z := new(Zipf)
 	if s <= 1.0 || v < 1 {
@@ -52,9 +51,12 @@ func NewZipf(r *Rand, s float64, v float64, imax uint64) *Zipf {
 	return z
 }
 
-// Uint64 returns a value drawn from the Zipf distributed described
+// Uint64 returns a value drawn from the Zipf distribution described
 // by the Zipf object.
 func (z *Zipf) Uint64() uint64 {
+	if z == nil {
+		panic("rand: nil Zipf")
+	}
 	k := 0.0
 
 	for {