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How can I create polygon of gaps/holes if I have several shapefiles. Do I really have to merge all layers, it it big amount of data (NEW YORK roadbed, buildings, water,parks etc)

I have ET geowizards to clean polygons or create gaps but I can only choose one layer. Merging all layers takes so long time.

maybe it is another way? erasing, clip with an background layer?.

Union with no gaps allowed worked but i need to be able to symbolize the gap polygon and i need to be able to select individual gap polygons.

any ideas?

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Can you explain exacly what you're trying to accomplish in greater depth. Most of your question focusses on the ideas you have and there's very little description of what you're actually "trying to do". I posted a link to an answer some of the other users gave me, but I'm not sure if you're trying to accoplish the same thing I was. – Dano Mar 2 '12 at 15:04

I agree that some additional details on what you end goal is for this would be helpful.

But, if i understand correctly you have successfully created your gap polygon but are unable to symbolize it because all your polygons are a single record. If so, you could just start and edit session and use the "explode" tool to create individual records for each gap polygon. This should allow you to symbolized the gaps to your liking.


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If I understand you correctly, you want to make a shapefile out of gaps / holes in your existing data sets; basically a shapefile of "what's not catured"? Look at some of the answers HERE. I'm not entirely certain this is what you're trying to do, but hopefully it gives you the answer you're after (or at least a starting point or some direction).

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I have solved this very problem, by creating a topology, (with Allow no gaps rule) and then exporting the errors to a featureclass.

If you are on ArcGIS10.1, you can use the inbuilt tool directly. Otherwise, you can use this tool, if you are on Arcgis 9.x

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A simple way would be to convert the vectors to rasters. Then calculate a resulting raster by summing up values of all rasters. The pixels with 0 values are the gaps. Convert it back to vector and you have your polygons.

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