comp.lang.idl-pvwave archive: archive » Re: REBIN needs explaining

Home » Public Forums » archive » Re: REBIN needs explaining

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

Re: REBIN needs explaining [message #41927 is a reply to message #41926]

Tue, 30 November 2004 16:53

David Fanning
Messages: 11724
Registered: August 2001

Senior Member

JD Smith writes:

> So here it has just 1 interval producing 10 points, and 10 points are
> duplicated from the last value. The manual also recommends the
> solution:
>
> If this effect is undesirable, use the INTERPOLATE function.

Well, I *would* use the INTERPOLATE function if I could
understand it. :-(

The REBIN documentation says this:

*************************************************
; A four point vector:
A = [0, 10, 20, 30]

; Expand by a factor of 3:
B = REBIN(A, 12)

PRINT, B
IDL prints:

0 3 6 10 13 16 20 23 26 30 30 30

Note that the last element is repeated three times. If this effect is
undesirable, use the INTERPOLATE function. For example, to produce 12
equally spaced interpolates from the interval 0 to 30:

B = INTERPOLATE(A, 3./11. * FINDGEN(12))
PRINT, B
IDL prints:

0 2 5 8 10 13 16 19 21 24 27 30
*************************************************

But,

IDL> Print, 3./11. * FINDGEN(12))
0.000000 0.272727 0.545455 0.818182 1.09091
1.36364 1.63636 1.90909 2.18182 2.45455 2.72727
3.00000

How in the world to *those* numbers, when applied to A, produce
the result I get? Seems like magic to me. :-(

Cheers,

David

--
David Fanning, Ph.D.
Fanning Software Consulting, Inc.
Coyote's Guide to IDL Programming: http://www.dfanning.com/

Report message to a moderator

[Message index]

		Re: REBIN needs explaining By: David Fanning on Wed, 01 December 2004 04:38
		Re: REBIN needs explaining By: Paolo Grigis on Wed, 01 December 2004 00:45
		Re: REBIN needs explaining By: b.hinrichsen on Wed, 01 December 2004 00:38
		Re: REBIN needs explaining By: Chris Lee on Wed, 01 December 2004 00:23
		Re: REBIN needs explaining By: David Fanning on Tue, 30 November 2004 16:53
		Re: REBIN needs explaining By: JD Smith on Tue, 30 November 2004 15:56

Previous Topic:	applications guis and licenses
Next Topic:	Re: applications guis and licenses

-=] Back to Top [=-

[ Syndicate this forum (XML) ] [

] [

]

Current Time: Sun Oct 12 00:33:34 PDT 2025

Total time taken to generate the page: 1.20165 seconds