show perl rand() with Asymptote

1 #! /usr/bin/perl

 2 use warnings;
 3 use strict;
 4 
 5 =comment
 6 
 7     用 Asymptote 来观察 perl 中 rand() 函数的随机性。
 8     需要安装配置好 Asymptote
 9 
10     从观察结果看，还是令人满意的，分布比较均匀
11 
12 =cut
13 
14 open(TT, '>', '__t.asy') or die $!;
15 print TT 'size(10cm, 0);', "\n\n";
16 
17 for (1 .. 1000) {
18     my $x = sprintf("%.2f", rand(200));
19     my $y = sprintf("%.2f", rand(200));
20 
21     print TT "dot(($x, $y));\n";
22 }
23 
24 print TT 'draw(box((0,0), (200,200)));', "\n";
25 close TT;
26 
27 system('asy __t.asy');