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 #55301]

Thu, 16 August 2007 03:13

Paolo Grigis
Messages: 171
Registered: December 2003

Senior Member

Gianguido Cianci wrote:
>> A graphical representation is also always useful...
>>
>> loadct,5
>> tvscl,shift(dist(512,512),256,256)
>>
>> Ciao,
>> Paolo
>
>
> Useful, but not sufficient in my case :-(
> In the case of dist(4,1), say, how do you get the values 0.00, 1.00,
> 2.00, 1.00 ?
>
> Never quite got it! :-(
>
> G
>

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

------------------

So dist[i,j] is the shortest distance from the euclidean
point with coordinates (i,j) to one of the points (0,0),
(0,m), (n,0) or (n,m).

Ciao,
Paolo

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: Wed Oct 08 18:52:14 PDT 2025

Total time taken to generate the page: 0.00447 seconds