# [GRASS-user] Calculating distance between 2 point vectors along a line vector

Helmut Kudrnovsky hellik at web.de
Sun Dec 13 12:21:21 PST 2015

```Otto Dassau-3 wrote
> Hi,
>
> v.net.allpairs could be a starting pioint:
> https://grass.osgeo.org/grass70/manuals/v.net.allpairs.html
>
> Regards,
> Otto
>
> Am Sat, 12 Dec 2015 14:31:48 -0800 (PST)
> schrieb Helmut Kudrnovsky <

> hellik@

> >:
>
>> Hi,
>>
>> given following data :
>>
>> - data 1 point vector , e.g. sample points along a river
>> - data 2 point vector, e.g.  point pollution Inputs in a river
>> - data 3 line vector, e. g. rivers or streams
>>
>> Any ideas how to calculate the distance between the points of data 1 and
>> data 2 along the vector lines in data 2?
>>
>>
>>
>> -----
>> best regards
>> Helmut

thanks.

after some testing: v.net.distance [1] does the job quite nicely.

- step 1: v.net operation=connect input=line points=samplepoints
output=line_samplepoints node_layer=3

- step 2: v.net operation=connect input=line_samplepoints
points=pollution_points output=line_samplepoints_pollutionpoints
node_layer=4

- step3: v.net.distance input=line_samplepoints_pollutionpoints
output=calculated_distance from_layer=3 to_layer=4

[1] https://grass.osgeo.org/grass71/manuals/v.net.distance.html

-----
best regards
Helmut
--
View this message in context: http://osgeo-org.1560.x6.nabble.com/Calculating-distance-between-2-point-vectors-along-a-line-vector-tp5241048p5241104.html
Sent from the Grass - Users mailing list archive at Nabble.com.
```