# HG changeset patch
# User Claus Gittinger <cg@exept.de>
# Date 934450951 -7200
# Node ID 037f3ceb4e0a6c938c67994e7d990934f80c429f
# Parent  2d3e914e5ae92cff22db132071958c44059a1a3c
checkin from browser

diff -r 2d3e914e5ae9 -r 037f3ceb4e0a Random.st
--- a/Random.st	Wed Aug 11 19:48:26 1999 +0200
+++ b/Random.st	Thu Aug 12 11:42:31 1999 +0200
@@ -186,6 +186,40 @@
 
 !Random class methodsFor:'testing'!
 
+bucketTest: randy
+    "A quick-and-dirty bucket test. Prints nbuckets values on the Transcript.
+     Each should be 'near' the value of ntries. Any run with any value 'far' from ntries
+     indicates something is very wrong. Each run generates different values.
+     For a slightly better test, try values of nbuckets of 200-1000 or more; 
+     go get coffee.
+     This is a poor test; see Knuth.   
+     Some 'OK' runs:
+           1000 1023 998 969 997 1018 1030 1019 1054 985 1003
+           1011 987 982 980 982 974 968 1044 976
+           1029 1011 1025 1016 997 1019 991 954 968 999 991
+           978 1035 995 988 1038 1009 988 993 976
+    "
+
+    | nbuckets buckets ntrys slot |
+
+    nbuckets := 20.
+    buckets := Array new: nbuckets.
+    buckets atAllPut: 0.
+    ntrys :=  1000.
+    ntrys*nbuckets timesRepeat: [
+            slot := (randy next * nbuckets) floor + 1.
+            buckets at: slot put: (buckets at: slot) + 1 ].
+    Transcript cr.
+    1 to: nbuckets do: [ :nb |
+            Transcript show: (buckets at: nb) printString, ' ' ]
+
+
+    "Execute this:  
+     Random bucketTest: Random new
+    "
+
+!
+
 chiSquareTest   
     " Chi-Squared Test - from R.Sedgewick's 1st ed. of 'Algorithms', 
             o N = number of samples
@@ -296,7 +330,6 @@
      in the range 0 .. 16r3FFFFFFF.
      From Sedgewick's 'Algorithms', based on Lehmer's method"
 
-    "the times: is a kludge - times does not convert to LargeInteger on overflow"
     self step.
     ^ seed
 
@@ -412,5 +445,5 @@
 !Random class methodsFor:'documentation'!
 
 version
-    ^ '$Header: /cvs/stx/stx/libbasic2/Random.st,v 1.21 1998-08-21 12:47:38 cg Exp $'
+    ^ '$Header: /cvs/stx/stx/libbasic2/Random.st,v 1.22 1999-08-12 09:42:31 cg Exp $'
 ! !