comp.lang.idl-pvwave archive: archive » Re: Repost of Vertex question...

Home » Public Forums » archive » Re: Repost of Vertex question...

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

Re: Repost of Vertex question... [message #25618 is a reply to message #25531]

Fri, 29 June 2001 07:01

Struan Gray
Messages: 178
Registered: December 1995

Senior Member

Craig Markwardt, craigmnet@cow.physics.wisc.edu writes:
> Brian Koss <bakoss@rainbow.uchicago.edu> writes:
>>
>> I have images of polygons connected edge to edge in a
>> quasiperiodic array, like the one I have attached to this
>> message... The images are black and white and the edges of
>> the polygons are distinguisable because they are straight
>> lines. I would love to be able to use IDL to find the
>> vertices in this image.
>
> Cute. Somehow I don't think this is a program that
> someone on the newsgroup can knock out in ten minutes.

Oh. I don't know.

A quasicrystal will have a limited number of vertex
orientations, which you can pick out by hand. Simply cut
out one of each type of vertex into it's own sub-image, do a
cross correlation between that and the whole image to find
where that type of vertex occurs, and add up the resulting
lists for each vertex type.

Alternately, if you know something about the scale
invariance of the quasicrystal, find the postions of the
edges or centres of the polygons in the same way, and then
use the quasicrystal's scaling properties to find the
vertices.

Struan

Report message to a moderator

[Message index]

		Re: Repost of Vertex question... By: Craig Markwardt on Thu, 28 June 2001 19:46
		Re: Repost of Vertex question... By: david[2] on Thu, 28 June 2001 17:06
		Re: Repost of Vertex question... By: Craig Markwardt on Mon, 02 July 2001 06:33
		Re: Repost of Vertex question... By: Struan Gray on Mon, 02 July 2001 04:05
		Re: Repost of Vertex question... By: Craig Markwardt on Fri, 29 June 2001 07:24
		Re: Repost of Vertex question... By: Struan Gray on Fri, 29 June 2001 07:01
		Re: Repost of Vertex question... By: Richard French on Fri, 29 June 2001 03:55
		Re: Repost of Vertex question... By: Martin Downing on Thu, 12 July 2001 08:41

Previous Topic:	Easy way to do superscripts, greek letters, etc.?
Next Topic:	Re: Easy way to do superscripts, greek letters, etc.?

-=] Back to Top [=-

[ Syndicate this forum (XML) ] [

] [

]

Current Time: Wed Oct 08 17:32:43 PDT 2025

Total time taken to generate the page: 0.00464 seconds