comp.lang.idl-pvwave archive: archive

Home » Public Forums » archive » Re: String Spliting

Show: Today's Messages :: Show Polls :: Message Navigator
E-mail to friend

Re: String Spliting [message #49361 is a reply to message #49358]

Wed, 19 July 2006 08:06

Michael Galloy
Messages: 1114
Registered: April 2006

Senior Member

ChristopherFlorio@gmail.com wrote:
> I am having a problem with the STRSPLIT function.
> I am using it to extract the file extension from a string where it
> might not be at the end.
> However in the process I am also eliminating addition elements, not
> found in the extension.
> For example
>
> file='Image.img'
> filter='*.img'
>
> file=STRJOIN(STRSPLIT(file,filter,/EXTRACT))
>
> file='Iae'
>
> desired output:
> file='Image'
>
> Is there a way, with the same input as above, not to extract individual
> parts of the name found in the filter/pattern?
>

From the docs, about a normal "filter" argument:

"One or more single characters, each of which is considered to be a
separator. String will be split when any of the characters is detected.
For example, if Pattern is " ," String will be split whenever either a
space or a comma is detected. In this case, IDL performs a simple string
search for the specified characters. This method is simple and fast."

But the filter can also be a regular expression:

IDL> file = 'Image.img'
IDL> filter = '\.img'
IDL> print, strjoin(strsplit(file, filter, /regex, /extract))
Image

The "\" is needed in the filter to escape "."'s special meaning (it
matches any character).

By the way, the docs on a regular expression "filter" argument:

"If the REGEX keyword is specified, Pattern is considered to be a single
regular expression (as implemented by the STREGEX function). This method
is slower and more complex, but can handle extremely complicated Pattern
strings."

If you want more information about regular expressions, see

http://michaelgalloy.com/2006/06/11/regular-expressions.html

Mike
--
www.michaelgalloy.com

Report message to a moderator

[Message index]

		Re: String Spliting By: Michael Galloy on Thu, 20 July 2006 06:37
		Re: String Spliting By: ChristopherFlorio on Thu, 20 July 2006 04:13
		Re: String Spliting By: Michael Galloy on Wed, 19 July 2006 13:03
		Re: String Spliting By: mmiller3 on Wed, 19 July 2006 12:49
		Re: String Spliting By: ChristopherFlorio on Wed, 19 July 2006 12:04
		Re: String Spliting By: JD Smith on Wed, 19 July 2006 10:39
		Re: String Spliting By: ChristopherFlorio on Wed, 19 July 2006 09:51
		Re: String Spliting By: Michael Galloy on Wed, 19 July 2006 08:06

Previous Topic:	Surface plots in spherical coordinates
Next Topic:	Re: mpfitexpr using functargs

-=] Back to Top [=-

[ Syndicate this forum (XML) ] [

] [

]

Current Time: Wed Dec 03 01:27:46 PST 2025

Total time taken to generate the page: 1.28096 seconds