Re^2: is rand random enough to simulate dice rolls?

[shmem]

If you could get a few people to post results for a variety of platforms, installations and Perl versions that they might have available, you may get something approaching a reasonable answer to your "every platform ... every version" question.

Well, here's an old platform and an old version ;-)

canis [shmem] /home/shmem > time perl -e 'my $iters = 100_000; my $run
+s = 6; for my $sides (qw{1 2 3 4 6 8 10 20 100}) { printf "%-5s", "D$
+sides:"; for (1 .. $runs) { my $tot = 0; for (1 .. $iters) { $tot += 
+int(rand $sides)+1; } print " ", $tot/$iters; } print "\n"; } '
D1:   1 1 1 1 1 1
D2:   1.5017 1.50273 1.49927 1.50004 1.50069 1.50234
D3:   2.00005 2.0013 1.99667 2.00228 2.00141 2.0018
D4:   2.49651 2.49254 2.50251 2.5008 2.49389 2.50032
D6:   3.4947 3.49803 3.4938 3.50231 3.50249 3.49613
D8:   4.50561 4.51195 4.51012 4.50395 4.4961 4.50096
D10:  5.52471 5.50722 5.50845 5.4933 5.4983 5.49319
D20:  10.51722 10.48846 10.52023 10.50762 10.48594 10.52206
D100: 50.43492 50.46292 50.4675 50.66063 50.35462 50.46591
293.510u 0.450s 4:54.97 99.6% 0+1599k 4+7io 1pf+0w
canis [shmem] /home/shmem > uname -a
SunOS canis 4.1.4 5 sun4m
canis [shmem] /home/shmem > perl -v

This is perl, version 5.004

Copyright 1987-1997, Larry Wall

Perl may be copied only under the terms of either the Artistic License
+ or the
GNU General Public License, which may be found in the Perl 5.0 source 
+kit.

SPARCstation voyager, cpu = SUNW,S240. Sorry, no PDP-11 available, and the Atari is out of order.

Update: looks like perl4 is significantly slower. But the numbers look right.

canis [shmem] /home/shmem > time perl4 -e '$iters = 100_000; $runs = 6
+; for $sides (1,2,3,4,6,8,10,20,100) { printf "%-5s", "D$sides:"; for
+ (1 .. $runs) { $tot = 0; for (1 .. $iters) { $tot += int(rand $sides
+)+1; } print " ", $tot/$iters; } print "\n"; }'
D1:   1 1 1 1 1 1
D2:   1.4976199999999999513 1.4995000000000000551 1.500839999999999951
+9 1.5009200000000000319 1.4983500000000000707 1.4992000000000000881
D3:   1.9988500000000000156 2.0010099999999999554 1.997360000000000024
+3 1.9947699999999999321 2.0022500000000000853 1.9987600000000000922
D4:   2.4961099999999998289 2.5017000000000000348 2.501459999999999794
+8 2.4986999999999999211 2.4970900000000000318 2.5005099999999997884
D6:   3.50016000000000016 3.4905300000000001326 3.5027200000000000557 
+3.4986999999999999211 3.4940500000000001002 3.4981499999999998707
D8:   4.5008200000000000429 4.4963499999999996248 4.499399999999999622
+ 4.505130000000000301 4.500880000000000436 4.4966600000000003234
D10:  5.5046299999999996899 5.4901400000000002422 5.493229999999999613
+2 5.4982899999999998997 5.4878000000000000114 5.481379999999999697
D20:  10.478590000000000515 10.511730000000000018 10.48712000000000088
+6 10.511749999999999261 10.520690000000000097 10.513320000000000221
D100: 50.332399999999999807 50.534730000000003258 50.68713999999999941
+8 50.558239999999997849 50.449489999999997281 50.479340000000000543
473.690u 154.350s 26:25.22 39.6% 0+4164k 0+7io 39159pf+0w
canis [shmem] /home/shmem > perl4 -v

This is perl, version 4.0

$RCSfile: perl.c,v $$Revision: 4.0.1.4 $$Date: 91/06/10 01:23:07 $
Patch level: 10

Copyright (c) 1989, 1990, 1991, Larry Wall

Perl may be copied only under the terms of either the Artistic License
+ or the
GNU General Public License, which may be found in the Perl 4.0 source 
+kit.