[GRASSLIST:7825] distance between two points

Is there a grass function that will calculate the distance between two points on a vector layer? How about between a point on a vector layer and a cell on a raster layer?

On Mon, Aug 08, 2005 at 03:08:30PM -0400, Jason Horn wrote:

Is there a grass function that will calculate the distance between
two points on a vector layer?

Yes.

- direct distance: v.distance
- along a vector network: v.net.path/d.path

How about between a point on a vector
layer and a cell on a raster layer?

- you may convert the cell center to a vector point (r.to.vect)
- then above functions

Markus

To put it simply:

I have a vector layer that contains a point of interest. I'd like to know the distance from that point to every cell in a raster layer that covers the same area. I did look through all the commands I did not find anything that allows one to compare features between vector and raster layers.

On Aug 8, 2005, at 3:56 PM, David Finlayson wrote:

Have you looked through the commands and not found what you need
there? These commands: v.distance, d.geodesic, d.measure, r.buffer,
r.distance all do a variation on the theme.

If these don't work, maybe you can describe what you are trying to
accomplish in more detail.

David

On 8/8/05, Jason Horn <jhorn@bu.edu> wrote:

Is there a grass function that will calculate the distance between
two points on a vector layer? How about between a point on a vector
layer and a cell on a raster layer?

--
David Finlayson
Marine Geology & Geophysics
School of Oceanography
Box 357940
University of Washington
Seattle, WA 98195-7940
USA

Office: Marine Sciences Building, Room 112
Phone: (206) 616-9407
Web: http://students.washington.edu/dfinlays