From: Heng Li <lh3@live.co.uk>
Date: Wed, 6 Apr 2011 16:19:14 +0000 (-0400)
Subject: added table.shuffle()
X-Git-Tag: ksprintf-final~58
X-Git-Url: http://git.kaiwu.me/postgresql/log/contrib/postgres_fdw/static/gitweb.js?a=commitdiff_plain;h=54004e39cf19a14254b45208d8e330de67c782b1;p=klib.git

added table.shuffle()
---

diff --git a/lua/klib.lua b/lua/klib.lua
index 5421d4e..ecb8baf 100644
--- a/lua/klib.lua
+++ b/lua/klib.lua
@@ -39,6 +39,7 @@
   string:split()
   io.xopen()
   table.ksmall()
+  table.shuffle()
   math.lgamma() >math.lbinom() >math.igamma()
   math.igamma() <math.lgamma() >matrix.chi2()
   math.erfc()
@@ -163,6 +164,13 @@ function table.ksmall(arr, k)
 	end
 end
 
+function table.shuffle(a)
+	for i = #a, 1, -1 do
+		local j = math.random(i)
+		a[j], a[i] = a[i], a[j]
+	end
+end
+
 --
 -- Mathematics
 --