comp.lang.idl-pvwave archive: archive » Another "How to efficiently do this in IDL" question

Home » Public Forums » archive » Another "How to efficiently do this in IDL" question

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

Re: Another "How to efficiently do this in IDL" question [message #78304 is a reply to message #78105]

Thu, 03 November 2011 14:56

JDS
Messages: 94
Registered: March 2009

Member

On Friday, October 21, 2011 6:15:09 PM UTC-4, robintw wrote:
>
> The other main question is that if I've got an array of points like the
> following:
>
> 1 3 3 5 6 2 1
> *
>
> What is an efficient way to check that there are at least two points on
> each side of the central point (marked with a star) that have a lower
> value than it. My original thought was to loop through the cells, but I
> suspect some fancy histogram command could do something to help with this...
>

You can find all the "5 point peaks" relatively efficiently:

wh=where(d gt ((m=median(d,3))) and smooth((d eq m)*(n-2),n-2) eq n-3)

n=5 in your case.

Report message to a moderator

[Message index]

		Another "How to efficiently do this in IDL" question By: Robin Wilson on Fri, 21 October 2011 15:15
		Re: Another "How to efficiently do this in IDL" question By: JDS on Thu, 03 November 2011 14:56

Previous Topic:	Pixel modification after classification
Next Topic:	Re: UTM Map Projection Produces Incorrect Results

-=] Back to Top [=-

[ Syndicate this forum (XML) ] [

] [

]

Current Time: Sun May 03 21:04:43 PDT 2026

Total time taken to generate the page: 2.23896 seconds