0

enter image description hereI have an issue where I have feature classes of groups of zip codes in different sectors of the US that I have created. I want to be able to define the outer boundary of these groups so I can create a single shape file (one polygon). I was going to use this new polygon to clip the original file.

Is there a way to take many polygons and create a file that only shows the outer extent of the group? And how would I go about such an endeavor?

  • What software are you using? If you're going for a polygon feature that's normally called a hull polygon (convex or concave). – Jason Scheirer Jul 14 '14 at 21:03
  • Hi, I'm using ArcGIS 10.2. – Ryan Jul 14 '14 at 21:13
  • 2
    Would you be able to edit your question to include whether your "feature classes of groups of zip codes" are points or polygons, please? – PolyGeo Jul 14 '14 at 21:29
  • My zip codes are polygons. 'Minimum bounding geometry tool' and 'feature envelope to polygon tool' provided output polygons that exceed the extent of my group and I need the exact external boundary of of my zip code polygons. Thanks! – Ryan Jul 14 '14 at 21:58
  • Can you provide a picture to show what you're after? Both of those tools are good suggestions, I'd like to see why they don't produce the required result and we can go from there. – Michael Stimson Jul 14 '14 at 22:21
4

In ArcGIS, use the Minimum Bounding Geometry tool. You have several options of which kind of "encompassing" geometry you'd like to get back to clip against. Just remember to use ALL for the group_option parameter if you only want one geometry back.

EDIT: Based on how I understand what you're asking for now, I think the dissolve tool is more appropriate. Dissolve on the same field that you are using to set up your class breaks.

1

Perhaps the Feature Envelope to Polygon tool will give you want you want. If you need to merge features first, you can run the Dissolve tool.

1

Easiest and quickest way I found is to clip a larger polygon (i.e. a county polygon) with your smaller polygon (i.e. a feature class of a group of voting districts, comprising one magisterial district, in my situation). This will give you a polygon of the outer boundaries but remove the inner boundaries. You will have to merge the feature groups tho, first. Then the clip will give that feature minus the inner boundaries.

1

Aggregate Polygons?
Combines polygons within a specified distance of each other into new polygons.

  • 2
    A good answer should include more detail on how the tool works and how it can be used to solve OP's question. Please edit to include a more detailed explanation. – lambertj Jan 3 '19 at 15:03

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.