markc@umd.edu

8-member dissolve

Discussion created by markc@umd.edu on Aug 12, 2011
Latest reply on Aug 16, 2011 by markc@umd.edu
Hi,

I have a shapefile that shows lakes, generated from raster.  Some lakes have portions that are only a single pixel wide and when converted to polygon appear as separate individual polygons adjacent on a diagonal.  The standard dissolve function will only dissolve those adjacent polygons whose sides are completely touching (i.e. only the 4 with full sides touching) and not those that are on a diagonal.  I want to dissolve these into a single polygon.  The data set is very large, hundreds of thousands of polygons, so can't do this by hand.  Is there any way to force either the raster to polygon tool or dissolve to accept the diagonal polygons as part of the same polygon?

(for whatever reason I can't post a picture here and I don't have a web server to put the figure on)

Any help would be much appreciated.

Best regards,

Mark

Outcomes