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The description (taken from GRASS) is unclear; please check the GRASS plugin for more clear descriptions

The optional output=name parameter to produce a vector of lines of minimum distance should be added

v.distance.toattr is not available from the list of modules

v.distance still does not work for me

Perhaps 6.4.3 will address that: http://trac.osgeo.org/grass/log/grass/branches/releasebranch_6_4/vector/v.distance

It would be ideal to make a test with a current GRASS 6.4.svn snapshot.

Markus Neteler - wrote:

Perhaps 6.4.3 will address that: http://trac.osgeo.org/grass/log/grass/branches/releasebranch_6_4/vector/v.distance

It would be ideal to make a test with a current GRASS 6.4.svn snapshot.

hi Marcus, were you referring to the "-a" parameter?

Victor Olaya wrote:

it works here (the algorithm executes), although the results are empty... One of the things this algorithm does is to update the input layer. That has no effect in SEXTANTE, since it is updating the layer imported in the mapset, not the orginal, so currently the algorithm does nt make much sense. Maybe it should be removed temporarily.

see may notes here

https://github.com/qgis/QGIS/pull/989#issuecomment-28645026

in GrassAlgorythm.py should be possible to add a special case for v.out.ogr when v.distance is run, and make it use as input not the layer created as "output" by v.distance, but instead one of the inputs ("from"), that after v.distance is run is now modified and contains the min distances. I wasn't able to create a clean patch, but this approach definitely works.

In v.distance.txt we should just describe better the "output" because otherwise it can confuse users, something like this:

OutputVector|output|Output layer ("from" layer with updated column)

Adding the dmin/dmax parameters do also work

ParameterNumber|dmin|Minimum distance or -1 for no limit|None|None|-1
ParameterNumber|dmax|Maximum distance or -1 for no limit|None|None|-1

On the other hand it is not clear to me why the line vector representing min distances comes out empty.

I would suggest also remove the "-a" parameter (Calculate distances to all features within the threshold), from v.distance.txt and v.distance.toattr.txt and eventually making a separate module:

*) when using the "-a" parameter the "from" vector is not updated

*) when using "-a" it should be possible to output the results into a table (dbf), problem is that seems GRASS can only output this file inside de mapset folder (any attempt to use a path fails), so the results can only be seen in the processing log. And also it can be take a long time to run when features in from/to are relatively many.

I would suggest also remove the "-a" parameter (Calculate distances to all features within the threshold), from v.distance.txt and v.distance.toattr.txt and eventually making a separate module:

probably this is not necessary as the distances are calculated referring to grass features "cats" and we know that anyway we remove this column when vectors are outputted, so this distances are not very re-usable.

85|9893|737.194183
85|9894|26.852766
86|7353|991.986074
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