File::Copy under OS/2

[p5sagit/p5-mst-13.2.git] / t / op / rand.t

diff --git a/t/op/rand.t b/t/op/rand.t
index 5c0eccf..6031f42 100755 (executable)
--- a/t/op/rand.t
+++ b/t/op/rand.t
@@ -2,28 +2,34 @@
 
 # From: kgb@ast.cam.ac.uk (Karl Glazebrook)
 
-print "1..4\n";
+print "1..6\n";
 
 srand;
 
-$m=0; 
+$m=$max=0; 
 for(1..1000){ 
    $n = rand(1);
-   if ($n<0 || $n>=1) {
+   if ($n<0) {
        print "not ok 1\n# The value of randbits is likely too low in config.sh\n";
        exit
    }
    $m += $n;
-
+   $max = $n if $n > $max;
 }
 $m=$m/1000;
 print "ok 1\n";
 
+$off = log($max)/log(2);
+if ($off > 0) { $off = int(.5+$off) }
+    else { $off = - int(.5-$off) }
+print "# Consider adding $off to randbits\n" if $off > 0;
+print "# Consider subtracting ", -$off, " from randbits\n" if $off < 0;
+
 if ($m<0.4) {
     print "not ok 2\n# The value of randbits is likely too high in config.sh\n";
 }
 elsif ($m>0.6) {
-    print "not ok 2\n# Something's really weird about rand()'s distribution.\n";
+    print "not ok 2\n# The value of randbits is likely too low in config.sh\n";
 }else{
     print "ok 2\n";
 }
@@ -49,4 +55,12 @@ if ($m<40 || $m>60) {
     print "ok 4\n";
 }
 
+srand(3.14159);
+$r = rand;
+srand(3.14159);
+print "# srand is not consistent.\nnot " if rand != $r;
+print "ok 5\n";
+
+print "# rand is unchanging!\nnot " if rand == $r;
+print "ok 6\n";