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Using v.dissolve in GRASS, I'd like to get a multipolyon as a result. However, I end up with distinct polygons with the same 'dissolve value.'

For example; lets assume I have two polygon features which are not touching each other spatially. Both have a 'DISS" value of 1. If I run v.dissolve on this DISS value, I get the same thing in the output as the input (i.e. two seperate polygons with a DISS value of 1). What I would like to be able to get is an output that contains one single multipolygon. How do I go about this?

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Please also say which GRASS GIS version you use... – markusN Dec 17 '12 at 19:50
Thanks markus; I am using GRASS 6.4.3RC1 (2012) via qgis/OSGeo4W – Darren Cope Dec 17 '12 at 20:14
up vote 3 down vote accepted

It looks like GRASS does in fact treat the result as a multipolygon, although QGIS displays it as separate features. I determined this by calculating the area on the feature(s) and they all came out to be the same for each DISS value. This is also hinted at in this post, where Radim responds:

The multi features are kept in GRASS but in QGIS represented as multiple features.

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