[GRASS5] d.vect.thematic and point diameters?

GRASS GIS GRASS GIS developer
1

Michael,
(cc list)

after having sucessfully generated the count column of
my disease incident map (number of cases per vector point),
I want to visualize it with the point diameter corresponding
to the number of cases for that point.

I thought to use d.vect.thematic for this, but don't
manage to do it. The legend comes nicely, but the
symbol size remains constant and doesn't vary with
the values of the selected attribute column.

Before starting to debug/add code, is it already
possible?

Thanks

Markus

2

The symbol size should change. There are lots of options. Did you pick
graduated points (rather than graduated colors) for thematic type?

Michael
______________________________
Michael Barton, Professor of Anthropology
School of Human Evolution and Social Change
Arizona State University
Tempe, AZ 85287-2402
USA

voice: 480-965-6262; fax: 480-965-7671
www: http://www.public.asu.edu/~cmbarton

From: Markus Neteler <neteler@itc.it>
Date: Thu, 11 Aug 2005 18:38:08 +0200
To: Michael Barton <michael.barton@asu.edu>
Cc: grass5 developers list <grass5@grass.itc.it>
Subject: d.vect.thematic and point diameters?

Michael,
(cc list)

after having sucessfully generated the count column of
my disease incident map (number of cases per vector point),
I want to visualize it with the point diameter corresponding
to the number of cases for that point.

I thought to use d.vect.thematic for this, but don't
manage to do it. The legend comes nicely, but the
symbol size remains constant and doesn't vary with
the values of the selected attribute column.

Before starting to debug/add code, is it already
possible?

Thanks

Markus

3

On Thu, Aug 11, 2005 at 10:46:04AM -0700, Michael Barton wrote:

The symbol size should change. There are lots of options. Did you pick
graduated points (rather than graduated colors) for thematic type?

Ah, thanks. I missed it, now it works like a charm.

Markus

4

Great!

Any thoughts on how to deal with the null values in a database column
problem. We don't want to treat these as 0's

Michael
______________________________
Michael Barton, Professor of Anthropology
School of Human Evolution and Social Change
Arizona State University
Tempe, AZ 85287-2402
USA

voice: 480-965-6262; fax: 480-965-7671
www: http://www.public.asu.edu/~cmbarton

From: Markus Neteler <neteler@itc.it>
Date: Fri, 12 Aug 2005 11:08:50 +0200
To: Michael Barton <michael.barton@asu.edu>
Cc: grass5 developers list <grass5@grass.itc.it>
Subject: Re: d.vect.thematic and point diameters?

On Thu, Aug 11, 2005 at 10:46:04AM -0700, Michael Barton wrote:

The symbol size should change. There are lots of options. Did you pick
graduated points (rather than graduated colors) for thematic type?

Ah, thanks. I missed it, now it works like a charm.

Markus