comp.lang.idl-pvwave archive: archive » Re: frequency distribution and bytscl

Home » Public Forums » archive » Re: frequency distribution and bytscl

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

Re: frequency distribution and bytscl [message #31377 is a reply to message #31376]

Wed, 10 July 2002 08:44

mchinand
Messages: 66
Registered: September 1996

Member

In article <aghiu4$kcb$1@newsreader.wustl.edu>,
Sean Raffuse <sean@me.wustl.edu> wrote:
> Hello,
>
> I want to stretch an image based on it's frequency distribution:
> stretched_image = bytscl(image, min=low, max=high)
> where low is the bottom 5th percentile and high is the upper 5th percentile.
> How can I get the values of the x percentile of a given array?
> thanks in advance,
>
> Sean
>

I think the PERCENT option of HIST_EQUAL function will do what you want.
It uses histogram and then TOTAL(histo,/CUMULATIVE) to find the cutoff
points.

Hope that helps,

--Mike

--
--
Michael Chinander University of Chicago
m-chinander@uchicago.edu (773)834-5101 (Voice) (773)702-0371 (Fax)

Report message to a moderator

[Message index]

		Re: frequency distribution and bytscl By: mchinand on Wed, 10 July 2002 09:43
		Re: frequency distribution and bytscl By: Liam E. Gumley on Wed, 10 July 2002 09:09
		Re: frequency distribution and bytscl By: mchinand on Wed, 10 July 2002 08:44

Previous Topic:	frequency distribution and bytscl
Next Topic:	Re: Using idlrt.exe

-=] Back to Top [=-

[ Syndicate this forum (XML) ] [

] [

]

Current Time: Sat Oct 11 04:42:35 PDT 2025

Total time taken to generate the page: 0.48110 seconds