From: Dave Baldwin <dave.baldwin@3dlabs.com>
Date: 2010-06-25T00:49:25+09:00
Subject: Re: Count substrings in string, scan too slow

http://en.wikipedia.org/wiki/Boyer–Moore_string_search_algorithm

If written in Ruby may not beat using the underlying library functions as they are written in C.

I have vague recollections of a ruby quiz being based on something like this
Dave.

On 24 Jun 2010, at 16:04, Danny Challis wrote:

> Hello everyone,
>   I need to count the number of times a substring occurs in a string.
> I am currently doing this using the scan method, but it is simply too
> slow.  I feel there should be a faster way to do this since the scan
> method is really designed for more advanced things than this.  I do not
> need to do regex matching or to process the matches, just count
> substrings.  So what I want is something like this:
> 
> s = "you like to play with your yo-yo"
> s.magical_count_method("yo") => 4
> 
> Once again, what I'm really looking for is something fast.  I've tried
> using external linux commands such as awk, but that was much much
> slower. Any ideas?
> Thanks,
> 
> Danny.
> -- 
> Posted via http://www.ruby-forum.com/.
>