comp.lang.idl-pvwave archive: archive » Re: For loop avoidance

Home » Public Forums » archive » Re: For loop avoidance - getting indices of real space

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

Re: For loop avoidance - getting indices of real space [message #81151]

Mon, 27 August 2012 03:37

Yngvar Larsen
Messages: 134
Registered: January 2010

Senior Member

On Thursday, 23 August 2012 22:58:48 UTC+2, simu...@gmail.com wrote:
> I have read and re-read until cross-eyed this post: http://www.idlcoyote.com/tips/forloops.html
>
>
>
> And yet, I still can't quite grasp at how I can solve my for loop problem. I think it might involve the use of modulo (MOD), but I'm not sure how. My question is, how can you grab the indices (i,j,k) of a 3D array in real space, and throw them into basically 3 1D arrays that is just a list of all the cells in the "proper" order (column-major).

There is a perfectly good builtin function in IDL to do this: ARRAY_INDICES.

IDL> nx = 15L
IDL> ny = 10L
IDL> nz = 20L
IDL> data = randomn(seed, nx,ny,nz)
IDL> ai = array_indices(data, lindgen(nx*ny*nz))
IDL>
IDL> help, ai
AI LONG = Array[3, 3000]

If you really need dimensions [3000,3], you can add
IDL> ai = transpose(temporary(ai))

--
Yngvar

Report message to a moderator

[Message index]

		Re: For loop avoidance - getting indices of real space By: Yngvar Larsen on Mon, 27 August 2012 03:37
		Re: For loop avoidance - getting indices of real space By: lecacheux.alain on Fri, 24 August 2012 07:41
		Re: For loop avoidance - getting indices of real space By: simulana on Fri, 24 August 2012 07:42
		Re: For loop avoidance - getting indices of real space By: simulana on Fri, 24 August 2012 07:25
		Re: For loop avoidance - getting indices of real space By: lecacheux.alain on Fri, 24 August 2012 02:32

Previous Topic:	Re: How would you measure the range of density on a graph using IDL?
Next Topic:	Re: image interplate and overlay lat/lon?

-=] Back to Top [=-

[ Syndicate this forum (XML) ] [

] [

]

Current Time: Wed Oct 08 15:31:55 PDT 2025

Total time taken to generate the page: 0.00434 seconds