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removing points from larger set

February 18 2009 | 2 comments
Categories: Map Data

Hi. This seems easy, but I can't seem to find a way to do this. I'm dealing with one feature class of home-ranges within which are isopleths representing intensity of animal use. I have another feature class of collection points.

Goal: to remove the highest use points from the larger set (the point attribute table does not have the home-range info).

I first broken apart the isopleths. Using the intersect tool, I identified which points fall within the highest use isopleths. Now I need to remove this set of points from the larger set. How can I do this?

Thanks for your help.

Mapping Center Answer:

Why not try this instead -- select all the points you DO want and write them to a file. To do that is easy -- just reverse your selection (to get the points in the lower use zones). Then right click the layer in the Table of Contents and select the Export function -- one option is to export only the selected features. If you have to make multiple files from your selections, then you can get them all back together again using the Append tool in ArcToolbox.

KUDOS! posted by Kate Gerndt on Feb 19 2009 8:09PM
Thanks for responding. I appreciate the suggestion. I forget about reversing selection, but I did end up stumbling upon the key search term, 'ERASE'. This tool proved to be an easy, accurate means of deleting a smaller subset of points from the larger set. And all of this is what we like about you guys.
Right -- thanks for the reminder! posted by Aileen Buckley on Feb 22 2009 1:08PM
Right you are! There is usually more than one way to skin the cat, so to speak, and sometimes you just get used to doing it the way you have for a while, so a reminder like this is great! Thanks!

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