comp.lang.idl-pvwave archive: archive » Re: Problem with dist function in IDL

Home » Public Forums » archive » Re: Problem with dist function in IDL

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

Re: Problem with dist function in IDL [message #55659 is a reply to message #55301]

Tue, 28 August 2007 11:26

David Fanning
Messages: 11724
Registered: August 2001

Senior Member

Paolo_Grigis writes:

> This program (not optimized) reproduces the functionality of DIST:
>
> ---------------------
>
> n=4
> m=5
>
> a=dist(n,m)
> b=fltarr(n,m)
>
> FOR i=0L,n-1 DO BEGIN
> FOR j=0L,m-1 DO BEGIN
> i2=min([i,n-i])
> j2=min([j,m-j])
> b[i,j]=sqrt(i2^2+j2^2)
> ENDFOR
> ENDFOR

I was just having a look at the BUTTERWORTH filter code in the IDL
library, and I notice that the ITTVIS programmer who wrote this
function uses the double FOR loop method to create the distance
function, rather than DIST.

What do you suppose he knows that we don't!?

Cheers,

David
--
David Fanning, Ph.D.
Fanning Software Consulting, Inc.
Coyote's Guide to IDL Programming: http://www.dfanning.com/
Sepore ma de ni thui. ("Perhaps thou speakest truth.")

Report message to a moderator

[Message index]

		Re: Problem with dist function in IDL By: Paolo Grigis on Thu, 16 August 2007 03:13
		Re: Problem with dist function in IDL By: Jean H. on Wed, 15 August 2007 17:34
		Re: Problem with dist function in IDL By: cgguido on Wed, 15 August 2007 16:23
		Re: Problem with dist function in IDL By: Paolo Grigis on Mon, 13 August 2007 03:06
		Re: Problem with dist function in IDL By: Michael Galloy on Sun, 12 August 2007 17:48
		Re: Problem with dist function in IDL By: David Fanning on Tue, 28 August 2007 11:26

Previous Topic:	controlling widget layout
Next Topic:	xyouts for iPlot?

-=] Back to Top [=-

[ Syndicate this forum (XML) ] [

] [

]

Current Time: Fri Oct 10 12:21:39 PDT 2025

Total time taken to generate the page: 1.28146 seconds