[GRASSLIST:210] Re: Fwd: Re: Help with distance

[Roy Sanderson]

As a slight extension to this, is there a simple way of calculating the
Euclidean distances (triangular matrix) between all pairs of sites stored
in a map.  One method is to dump out the site coords, then push it through
a C-prog, but is there a GRASS command that does the trick?

Many thanks
Roy

At 10:11 27/05/03 +0200, Radim Blazek wrote:
>On Monday 26 May 2003 18:17, you wrote:
>> I'm trying to calculate the distance from one point to another
>> along a street/vector layer. I was wondering if grass can help me with
>> this.
>
>v.distance in version 5.1 reports also the distance along the line.
>If you have crossroads (intersections) between two points, you can consider
>to preproces street map and create one line for each street. Something like:
>
>for CODE in echo "select distinct str_cd from viapri" | db.select -c`
>do
>    v.extract -t input=viapri output=viapri_sel where="str_cd = $CODE"
>    v.build.polylines input=viapri_sel output=viapri_p1
>    v.patch -a input=viapri_p3 output=viapri_pol
>done
>
>Radim
>
>
>