4 Replies Latest reply on Apr 25, 2012 6:59 AM by justgis

    create one polygon from many polygons

      Does anyone have any idea how I could create one large polygon from many smaller polygons. I've tried the Merge and Union but the output is not what I need. thanks for any help!
      ArcGIS10 on Vista
        • Re: create one polygon from many polygons
          Are you trying to build one large seamless polygon from several?

          Look at using the Dissolve tool.
          • Re: create one polygon from many polygons
            Thank you. I was just going to reply to my own question with, "Nevermind, I just remembered the dissolve tool!"
            • Re: create one polygon from many polygons
              I came across this post when having a similar issue
              I have cadastral lots and there are a few lots that in the attributes display as the same feature however the polygons are broken up into about 5 smaller polygons

              A few problems that I am having with the dissolve tool
              a) the one field I would use for unique values has some empty fields and therefore not really usable for dissolve
              b) if I was to get the dissolve to work for my problem how do I get all my attributes back that were lost doing the dissolve without adding any extra fields??
              • Re: create one polygon from many polygons
                I may not be able to answer everything you are asking, but I'm going to try.
                a) You could use your select tool and dissolve only the polygons within a certain location. If you have features selected from a feature class, the dissolve tool will only dissolve the selected features.
                b) When you do a dissolve on many polygons with differing values in a field, the dissolve will maintain each unique value for the field(s) you selected. You will still have many polygons within one feature class or shapefile and could possibly end up with as many polygons as you began with.

                I hope this helps.