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I am getting an extension error when I try and intersect some points and polygons.

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Here is a photo of what I am trying to intersect:

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Any help is appreciated.

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Are you using geographic coordinates or a projection? If there are no other obvious problems (and based on comments it sounds like there are not), I would try using a projection. –  djq May 13 '12 at 16:19
Is "extension error" a typo? If so, could be worth correcting. –  PolyGeo May 14 '12 at 1:02

2 Answers 2

I suspect that your input files are in two different coordinate systems. I don't think that intersect does a projection-on-the-fly prior to intersection. A visual inspection won't reveal this, ensure that they have the same coordinate system.

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This is not true. At least in ArcGIS 10.0. Possibly in previous versions but I am not sure. I have tried it using two layers even with different GCP which needs transformation method - intersection is working OK. So, it does projection-on-the-fly. –  Alex Markov May 13 '12 at 15:24
I have had the problem that Dan describes on ArcGIS 9.1 & 9.3 (not certain if it exists on ArcGIS 10.0). –  djq May 13 '12 at 16:07
Interesting. At least they fixed it in 10.0 :) –  Alex Markov May 13 '12 at 16:11
A screenshot of the Coordinate System tab from the Data Frame Properties with these two Layers expanded would give us a chance to see what coordinate system(s) the underlying data is stored in. –  PolyGeo May 14 '12 at 5:24

Actually, it is said there that your points and polygons don't intersect at all and thus you have "empty output".

You can check intersection visually by loading both layers - do you see any point inside polygons? Also check your intersection settings when running Intersect tool.

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Here is a photo of what I am trying to intersect. The coordinate systems are the same. I add an excel sheet then click on display XY data and select the same coordinate system as the polygons. Everything looks exactly like it's supposed to. Not sure what I am doing incorrectly. i.imgur.com/BYJ1w.png Thank you for your help! –  and_by May 13 '12 at 16:01
Have you tried to save XY data (points) to external feature class (shp, GDB) ? and then use it the Intersect tool. –  Alex Markov May 13 '12 at 16:10
Yuppers. That's how I am able to keep the table attributes. When I save as a shp file. Here are two more photos when I try to investigate the intersection error. I have no idea what they mean. i.imgur.com/fSUfA.png i.imgur.com/D8VkC.png –  and_by May 13 '12 at 16:14
Have you set any Environment Variables before executing Intersect tool? What coordinate system is used for your data? –  Alex Markov May 13 '12 at 16:23
I have not set any variables. I tried setting the XY variables to decimal degrees which is what they are for both the polygons and points. But it made no difference. –  and_by May 13 '12 at 16:57

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