From: ptkwt@... (Phil Tomson)
Date: 2003-09-23T05:31:16+09:00
Subject: Re: Performance: Ruby vs Java

In article <3f6e50b5$0$48907$edfadb0f@dtext02.news.tele.dk>,
Thomas Sondergaard <thomas@FirstNameGoesHereSondergaard.com> wrote:
>The difference is that ruby is interpreted and has a dynamic nature that
>makes it difficult to optimize (or so I understand), while java is jitted
>and for this single non-OO example it is probably as fast as C.
>
>I can't resist the temptation of plugging my own project rubydotnet, which
>allows you to implement such performance critical code in a .net language.
>
>CS_SCRIPT = <<-EOF
>    int n = (int) args[0];
>    for (int i=0; i<n-1; ++i)
>      for (int j=0; j<n-1; ++j)
>        if (j*i == n)
>          return false;
>    return true;
>  EOF
>
>def isPrime(n)
>  cs_eval(CS_SCRIPT, n)
>end
>
>puts isPrime(2)
>puts isPrime(4)
>puts isPrime(7)
>puts isPrime(25)
>puts isPrime(400003)
>
>On my laptop (3ghz P4):
>$ time ruby prime.rb
>true
>false
>true
>false
>false
>
>real    0m0.666s
>user    0m0.015s
>sys     0m0.000s
>

Or, for those of us not on a .NET platform (Windows) or those of us who 
are wary of it... 

You could do something very similar using Ryan Davis' RubyInline package.

http://sourceforge.net/projects/rubyinline/

Phil