comp.lang.idl-pvwave archive: archive » Re: 3-dimensional integration? [IDL 5.4]

Home » Public Forums » archive » Re: 3-dimensional integration? [IDL 5.4]

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

Re: 3-dimensional integration? [IDL 5.4] [message #35533 is a reply to message #35521]

Tue, 24 June 2003 07:18

Ingo Salzmann
Messages: 10
Registered: December 2002

Junior Member

Thanx! Unfortunately I forgot to mention, that my data points are
irregularely spaced. I would choose the approach to Triangulate [...]
TRIGRID [...] the data and then follow your hint. But ... what is the
relationship between the old irregularely spaced points described by their
(x,y,int) tuples and the new points within the (n,n,int) array? Are these
coordinates normalized?
Thank you!

"Timm Weitkamp" <timm.weitkamp@nowhere.edu> schrieb im Newsbeitrag
news:Pine.LNX.4.44.0306231600060.1635-100000@localhost.local domain...
> Oops! When I just wrote,
>
>> Circular regions take more than one line, but are easily doable too.
>> Assume that r is the radius of the circle over which you want to
>> integrate (in pixels). Then you should do something like this:
>>
>> dim = SIZE(data, /DIMENSIONS)
>> xarr = findgen(dim[0]) # (1+fltarr(dim[1]))
>> yarr = findgen(dim[1]) ## (1+fltarr(dim[0]))
>> rarr = SQRT((xarr-x)^2 + (yarr-y)^2)
>> idxList = WHERE(rarr LE r, npix)
>> IF npix NE 0 THEN tot = TOTAL(data[idxList])
>
> ... I hit the "send" key too early. The code above works, but its last two
> lines can (and should) be merged into the more elegant
>
> tot = TOTAL( (rarr LE r) * data )
>
> I think this way of directly using a logical expression for indexing,
> which in many cases I find very handy, is sometimes ignored by the
> worshipers of WHERE.
>
> Timm
>
> --
> Timm Weitkamp <http://people.web.psi.ch/weitkamp>
>

Report message to a moderator

[Message index]

		Re: 3-dimensional integration? [IDL 5.4] By: Timm Weitkamp on Wed, 25 June 2003 01:08
		Re: 3-dimensional integration? [IDL 5.4] By: Ingo Salzmann on Tue, 24 June 2003 07:18
		Re: 3-dimensional integration? [IDL 5.4] By: Timm Weitkamp on Mon, 23 June 2003 07:04
		Re: 3-dimensional integration? [IDL 5.4] By: Timm Weitkamp on Mon, 23 June 2003 06:36

Previous Topic:	Re: sec : U Re: Sinc interpolation
Next Topic:	Re: How to do nested objects??

-=] Back to Top [=-

[ Syndicate this forum (XML) ] [

] [

]

Current Time: Fri Oct 10 12:33:54 PDT 2025

Total time taken to generate the page: 1.84331 seconds