To aggregate features based on specified attributes.
6
votes
3answers
3k views
Is there a dissolve function in PostGIS other than st_union?
I'm looking for a function to dissolve shared boundaries between polygon features in a table. ST_UNION() almost does what I'm looking for, but it creates a multipolygon from all polygons in the layer ...
3
votes
2answers
403 views
Batch Dissolve Polygons based on Attributes in QGIS or FWTools
I was wondering if anyone can help with batching a dissolve. I have a few hundred polygon shapefiles that I want to dissolve based on an attribute. I would like to do this in QGIS or FWTools. Any ...
5
votes
4answers
1k views
Dissolve ploygons in QGIS or Grass to new polygons of defined population sizes
I have a shapefile with 3800 polygons representing the smallest administrative areas in Ireland. Many of these, in rural areas, have tiny populations, under 100 people. In urban areas, all would have ...
5
votes
3answers
955 views
Is there an ArcGIS tool equivalent to “Dissolve” that can be used on tables?
I have a data table that I need to trim down, merging records which have the same value in an ID field and performing a couple math operations on various other fields (summing, averaging). The ...
3
votes
0answers
549 views
How to create point labels from midpoints of road polylines in QGIS?
Heres what i want to achieve: i have a roading polyline layer (singlepart ie has several features per road, grouped by an id field), and i want to (after merging the parts) find the mid point of the ...
