From: Robert Klemme <shortcutter@...>
Date: 2007-06-12T20:05:08+09:00
Subject: Re: extracting numbers from a string

On 12.06.2007 09:32, come wrote:
> If you just want to extract one number from a string, you could write
> something like :
> 
> if a="DSC_1234.jpg"
> 
> then a[/\d+/] will give you the first longest string of numbers, so
> 1234.
> 
> If you want to be more precise, you could use parenthesis to extract
> the exact portion you want, like :
> 
> a[/DSC_(\d+)\.jpg/,1] (<=> a.match(/DSC_(\d+)\.jpg/)[1])
> 
> or even : a[/\ADSC_(\d+)\.jpg\Z/,1]

Or even simpler

irb(main):001:0> "DSC_1234.jpg"[/\d+/]
=> "1234"
irb(main):002:0> Integer("DSC_1234.jpg"[/\d+/])
=> 1234

Kind regards

	robert