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deriving contour intervals

September 21 2010 | 3 comments
Categories: Map Data

I thought I could define a field with only decimals and then divide the Elevation by 200 to get a contour interval. If my field was only decimals then anything that was zero and not a decimal value would be a contour interval. The trouble is I can't seem to define a field with only decimal values. I tried a Precision of 1, Scale of 1 but the calculation comes out with integer values, not the decimal values. Any ideas?

Mapping Center Answer:

I suggest you download a tool that has been created to do this -- it is available from the Community Maps Template and Tool Gallery. This should do the trick for you. Its predecessor was a tool that we used to have on Mapping Center but we no longer offer it for download here.

Note that you can modify the tool that you download to create the index contours at whatever intervals you want.

Another useful resource for this tool posted by Mamata Akella on Sep 22 2010 3:23PM
On the Community Maps Resource Center, there are several videos that you will find useful as well while using these tools. You can access the videos at:

The one that you will watch to learn more about this tool is titled "Creating and Indexing Contours for the Community Map".
v10 posted by Arthur Crawford on Sep 23 2010 2:23PM
If you are using ArcGIS 10, there is another version of the tool that has been updated I can send you.
ArcGIS 10 posted by Arthur Crawford on Sep 27 2010 10:01AM
ArcGIS 10 version has been loaded to the above Tool Gallery.

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