Re: plotting variable on xy axis

• To: Jacky Saint <saintjacky@xxxxxxxxxxx>
• Subject: Re: plotting variable on xy axis
• From: "From: Bill Hibbard <hibbard@xxxxxxxxxxxxxxxxx>" <billh@xxxxxxxxxxxxx>
• Date: Fri, 16 Feb 2001 15:04:36 -0600 (CST)

Hi Jacky,

>    I would like to know if anyone has successfully plotted temperature (or 
> someother variable) with respect to longitude and latitude. Please can 
> someone give me some hints on how I can accomplish this. My aim is to come 
> up with a contour graph, where the position of a weather station is defined 
> using longitude and latidude, and the data i.e. temperature will then be 
> shown as a contour (presumably using VisAD's contour class). So for every 
> weather station there will be a point on the map, my problem is to specify 
> the location using some sort of array or tuple, also the data needs to be 
> stored about temperature, wind, etc. I have looked at the examples i.e 
> P4_01, P3_0x, etc and tried modifying them to meet my need, but I have done 
> so with little success
>    I know this is not uncommon and has been done before, so I would 
> appreciate it if someone can tell me how I can accomplish my task, or where 
> I should be looking at.

Start with P3_05.java from Ugo's tutorial, but substitute
an Irregular2DSet for the Linear2DSet in domain_set.
Something like:

  int n = ... // numbber of weather stations
  float[][] samples = new float[2][n];
  for (int i=0; i<n; i++) {
    samples[0][i] = ... // latitude of station i
    samples[1][i] = ... // longitude of station i
  }
  domain_set = new Irregular2DSet(LatitudeLongitudeTuple, samples);

Then also:

  float[][] flat_samples = new float[1][n];
  for (int i=0; i<n; i++) {
    flat_samples[0][i] = ... // temperature at station i
  }

Good luck,
Bill
----------------------------------------------------------
Bill Hibbard, SSEC, 1225 W. Dayton St., Madison, WI  53706
hibbard@xxxxxxxxxxxxxxxxx  608-263-4427  fax: 608-263-6738
http://www.ssec.wisc.edu/~billh/vis.html

• Follow-Ups:
  • Re: plotting variable on xy axis
    • From: Tom Whittaker

• References:
  • plotting variable on xy axis
    • From: Jacky Saint