comp.lang.idl-pvwave archive: archive

Home » Public Forums » archive » MPFIT .TIED

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

Re: MPFIT .TIED [message #92280 is a reply to message #92278]

Tue, 10 November 2015 07:49

Dick Jackson
Messages: 347
Registered: August 1998

Senior Member

On Tuesday, 10 November 2015 07:08:15 UTC-8, wouter.sc...@gmail.com wrote:
> Dear All,
>
> I'm using MPFITFUN to find Gaussian shapes among some datasets. Mostly I'm interested in 2D Gaussian shapes (i.e. having a sigma-x and sigma-y). Additionally, I would like to tie both Gaussian sigma parameters to eachother in the sense that sigma-x cannot be bigger than e.g. 5*sigma-y, and vice versa as well (e.g. sigma-y cannot be bigger than 5*sigma-x).
>
> As I understand I can tie one parameter to another by specifing the parinfo[X].tied. The examples show how I can set one parameter equal to another. However, I have not been successfull in specifing a tied relation that covers a certain range (.2*Sx < Sy <= Sx < 5*Sy). Is this even possible?
>
> Thanks in advance!
> Cheers,
>
> Wouter

Hi Wouter,

I think what will work is to have one of the two (say, Sx) be a regular parameter, and have a "ratio" parameter (say, SyOverSx) that might start at 1.0 and be limited (using parinfo.limits and parinfo.limited) to [0.2, 5.0]. Then in your function, compute Sy as (Sx * SyOverSx) and use that. Sy and Sx will always stay within the relative range you're looking for.

I know this was brief, but does it give you enough to go on?

Cheers,
-Dick

Dick Jackson Software Consulting Inc.
Victoria, BC, Canada --- http://www.d-jackson.com

Report message to a moderator

[Message index]

		MPFIT .TIED By: wouter.schellekens on Tue, 10 November 2015 07:08
		Re: MPFIT .TIED By: Dick Jackson on Tue, 10 November 2015 07:49
		Re: MPFIT .TIED By: Craig Markwardt on Thu, 12 November 2015 11:08
		Re: MPFIT .TIED By: wouter.schellekens on Sat, 14 November 2015 11:20

Previous Topic:	IDLRT error - attempt to call undefined procedure
Next Topic:	TRIANGULATE's bug?

-=] Back to Top [=-

[ Syndicate this forum (XML) ] [

] [

]

Current Time: Wed Oct 08 17:55:36 PDT 2025

Total time taken to generate the page: 0.00953 seconds