[GRASS-dev] [GRASS GIS] #3848: Unexpected error with v.what.rast and v.rast.stats

[GRASS GIS]

#3848: Unexpected error with v.what.rast and v.rast.stats
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 Reporter:  micha        |      Owner:  grass-dev@…
     Type:  enhancement  |     Status:  new
 Priority:  normal       |  Milestone:  7.6.2
Component:  Default      |    Version:  unspecified
 Keywords:               |        CPU:  Unspecified
 Platform:  All          |
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 In general vector modules do not check or honor region settings. (The
 exception is v.to.rast, and this is specifically mentioned in the manual).
 However both v.rast.stats and v.what.rast require that the computational
 region covers the vector being queried.

 When running either of these modules with region settings that do **not**
 cover the vector, the error messages are unhelpful, even misleading:

 {{{
 micha at TP480:~$ v.what.rast weir7 rast=dem_4m col=dem type=centroid
 Reading features from vector map...
 No features of type (centroid) found in vector map <weir7>

 micha at TP480:~$ v.rast.stats weir7 rast=dem_4m column_pref=dem
 ERROR: No categories found in raster map
 }}}

 I suggest to add text to the man page of both, similar to the explanation
 in v.to.rast:

       v.to.rast will only affect data in areas lying inside the boundaries
 of the current geographic region.  A grid cell belongs to the area where
 the grid cell center falls into.

        Before running v.to.rast, the user should therefore ensure that the
 current geographic region is correctly set and that the region resolution
 is at the desired level.

 In addition, it would be helpful to modify the code of both modules to
 check region settings and output a relevant error message if the vector is
 outside the current region.

-- 
Ticket URL: <https://trac.osgeo.org/grass/ticket/3848>
GRASS GIS <https://grass.osgeo.org>