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I am trying to run a raster calculator, but it failed. I believe that ArcGIS 10 does not understand when I use the variable resolution. What do I need to put in its place?

I took the equation from this sheet USLE from North Carolina State University and checked on 2.3 for ArcGIS 8.1.

Here is the code I used:

Power (("flowaccNW") * resolution/22.1, 0.6) * Power(Sin("slope_degnw") * 0.01745) / 0.09, 1.3

I am using ArcGIS 10 SP4 using the Map Algebra raster calculator.


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If you look at the equation and it says "resolution" I took that from the sheet and ran with it and it failed. The ArcGIS said resolution does not defined. It made me think that ArcGIS does not understand, so I instead put down 10 as it is the DEM with 10 m. Get it ? – PROBERT Dec 5 '12 at 20:21
up vote 5 down vote accepted

Type your resolution of raster, not "resolution". Also, don't type +*/= by keyboard. Use raster calculator buttons. Here's how to set the resolution of your raster :

  1. Right-click your raster, and click Properties.
  2. Go to Source tab.
  3. Change Cellsize(X,Y) to set your resolution. enter image description here
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It will not work, wetland. – PROBERT Dec 5 '12 at 20:25
your second power must have two parameters – wetland Dec 5 '12 at 20:35
see second power parentheses – wetland Dec 5 '12 at 20:37
like this 10,10 ? – PROBERT Dec 5 '12 at 20:37
I try this and it's work : Power("stream" * 10 / 22.1,0.6) * Power(Sin("slope") * 0.01745 / 0.09,1.3) – wetland Dec 5 '12 at 20:38

You can use the GISus-M to calculate LS-factor.

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