topic Re: Converting DEM elevation range into a polygon in Data Management Questions

Converting DEM elevation range into a polygon

JoshuaBenton — Sun, 11 Nov 2012 01:06:03 GMT

I need to be able to convert an elevation range in a DEM into a polygon and I am having a heck of a time figuring out how to use the reclass tool. I am not sure how to create the remap table! Is anyone know of how to make this happen?

Re: Converting DEM elevation range into a polygon

JakeSkinner — Mon, 12 Nov 2012 14:42:10 GMT

Hi Joshua,

You can accomplish this using the Reclassify tool in Spatial or 3D Analyst toolbox. Open the tool, select your DEM for the input, and then click 'Classify'. Set the classes to 3 and click OK. Specify one of the 'Old Values' range to your desired elevation range that you want the polygon to be. For example, if your DEM has values from 1.5 - 58.7, and you're interested in values 20-30, then you should specify the Old Values to be in ranges:

0 - 19.9
20.0 - 30.0
30.1 - 58.7

The new values would default to 1, 2, and 3. After your new raster is created, you can open the attribute table and select Values = 2. Next run the Raster to Polygon tool on the selection and you will have your new polygon.

Re: Converting DEM elevation range into a polygon

JoshuaBenton — Tue, 20 Nov 2012 04:00:38 GMT

Hi Joshua,

You can accomplish this using the Reclassify tool in Spatial or 3D Analyst toolbox. Open the tool, select your DEM for the input, and then click 'Classify'. Set the classes to 3 and click OK. Specify one of the 'Old Values' range to your desired elevation range that you want the polygon to be. For example, if your DEM has values from 1.5 - 58.7, and you're interested in values 20-30, then you should specify the Old Values to be in ranges:

0 - 19.9
20.0 - 30.0
30.1 - 58.7

The new values would default to 1, 2, and 3. After your new raster is created, you can open the attribute table and select Values = 2. Next run the Raster to Polygon tool on the selection and you will have your new polygon.

Thank you for your reply! I figured it our doing the same thing and I also learned that there is a big difference between the Reclassify and Reclass tools as well.