comp.lang.idl-pvwave archive: archive » Array multiplication: implicit loop query

Home » Public Forums » archive » Array multiplication: implicit loop query

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

Re: Array Multiplication [message #79659 is a reply to message #26191]

Sun, 25 March 2012 08:09

lecacheux.alain
Messages: 325
Registered: January 2008

Senior Member

On 25 mar, 11:22, IDL beginner <moxam...@gmail.com> wrote:
> Dear All,
>
> I have the following question. Let's say we have a vector A and matrix
> array B so that:
>
> A = [1, 2, 5, 2, 3]
>
> B = [[2, 4], [1, 9]]
>
> I want to multiply each element of the vector A with the matrix array
> B but WITHOUT using a FOR loop. Is that possible??? I need to do so in
> order to save execution time.
>
> The output result should be an array C with dimensions C[2, 2, 5, 1].
>
> Any help is appreciated.
>
> MD
>
>

C = reform(reform(B, 4, OVER=over) # A, 2, 2, 5)

Regarding any optimization, using over=1 is faster, but will change
dimensions of B; using over=0 will keep B unchanged, but a temporary
copy of B is created.
alx.

Report message to a moderator

[Message index]

		Array multiplication: implicit loop query By: george on Fri, 10 August 2001 03:56
		Re: Array multiplication: implicit loop query By: bennetsc on Tue, 14 August 2001 23:57
		Re: Array multiplication: implicit loop query By: Richard Younger on Mon, 13 August 2001 13:59
		Re: Array multiplication: implicit loop query By: david[2] on Mon, 13 August 2001 11:52
		Re: Array multiplication: implicit loop query By: Richard Younger on Mon, 13 August 2001 11:37
		Re: Array multiplication: implicit loop query By: david[2] on Mon, 13 August 2001 07:55
		Re: Array multiplication: implicit loop query By: Craig Markwardt on Mon, 13 August 2001 06:58
		Re: Array multiplication: implicit loop query By: Paul van Delst on Mon, 13 August 2001 06:46
		Re: Array Multiplication By: Craig Markwardt on Sun, 25 March 2012 12:58
		Re: Array Multiplication By: lecacheux.alain on Sun, 25 March 2012 08:09

Previous Topic:	Coyote Library Updates
Next Topic:	Ask Mr. Cosmology

-=] Back to Top [=-

[ Syndicate this forum (XML) ] [

] [

]

Current Time: Sun Oct 12 03:58:03 PDT 2025

Total time taken to generate the page: 0.72701 seconds