comp.lang.idl-pvwave archive - RDF feed
type: channel
description: Messages from Usenet group comp.lang.idl-pvwave, compiled by Paulo Penteado
items: Shaded circles request.
items: Re: Shaded circles request.

Shaded circles request.
type: item
description: Hi, apologies in advance for an almost 'do my work' question, but I'm a bit stumped as to where to start with something. I wish to draw a plot with North-South and East-West axes upon which is drawn an incomplete grid of points. For each point I wish to have a circle drawn which is filled with a colour indicating the strength of the data point. Problems with this: (1) I want to label the axes with a minimum of fuss, so I'd like to preserve their values (not 0->array size) from the start. (2) How can I draw filled circles? (3) How can I get the filled cirles to automatically scale according to their value? Mmm, not as clear as I wished. You see I had a program to use TRIANGULATE and TRIGRID to remap my 2d array of data onto a large grid and then print that as filled contours, however my data is strictly not from points, its from a 'region', hence the filled circle alternate approach. The problem is that I'm finding it very difficult to do, I basically can't get started. Any advice? I can't quite think of an approach for this. E-mail and post please, my newserver does tend to pass out from excitment now and again and, as this is work related, I'd rather not miss a post that way. Thanks. -- David Kennedy, Dept. of Pure & Applied Physics, Queen's University of Belfast Email: D.Kennedy@Queens-Belfast.ac.uk | URL: http://star.pst.qub.ac.uk/~dcjk/ Hi! I'm a .signature virus! Copy me into yours and join the fun!
creator: D.Kennedy
date: 1997-01-27T08:00:00-00:00

Re: Shaded circles request.
type: item
description: David Fanning gave good tips for the original post from David Kennedy and supplied source code to return circle coordinates. The code uses a for loop to calculate the coordinates. It is generally better to use IDL's implicit array handling. An IDL function using my preferred method would look like: function circle, xcenter, ycenter, radius a = (2*!pi/99.)*findgen(100) x = xcenter + radius * cos(a) y = ycenter + radius * sin(a) return, transpose([[x],[y]]) end Best regards Kevin -- Kevin Ivory Tel: +49 5556 979 434 Max-Planck-Institut fuer Aeronomie Fax: +49 5556 979 240 Postfach 20 mailto:kivory2@gwdg.de D-37189 Katlenburg-Lindau, GERMANY http://www.gwdg.de/~kivory2/
creator: Kevin Ivory
date: 1997-01-28T08:00:00-00:00