From: come <come.news@...>
Date: 2007-06-12T16:35:03+09:00
Subject: Re: extracting numbers from a string

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]




On 12 juin, 08:45, Matt Jones <mattjonesph...@gmail.com> wrote:
> I have filenames from various digital cameras:  DSC_1234.jpg,
> CRW1234.jpg, etc.  What I really want is the numeric portion of that
> filename.  How would I extract just that portion?
>
> I expect it to involve the regex /\d+/, but I'm unclear how to extract a
> portion of a string matching a regex.
>
> Thank you
>
> --
> Posted viahttp://www.ruby-forum.com/.