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Working with Rasters

 In this last lab assignment for GIS Programming, I learned how to work with rasters using the arcpy.sa (Spatial Analysis) module. Our goal was to create a single raster image that met the following goals through the original dataset: 

  • Forest landcover (classifications 41, 42, and 43) 
  • Slope between 5° and 20° •
  • Aspect between 150° and 270°
To achieve these goals, I created five temporary rasters files and then combined them into one raster layer. I came across a couple of issues while creating my script for this assignment. 

The first issue I came across was I had 1,2,3 as the second number component in the RemapValue statement. I had missed the part in the script template that stated to assign all the new values to 1.

My second major issue was also caused by skipping a line. I did not add the line to create the elevation raster. This gave me some very interesting issues. While the script ran through all the way, whenever I tried to map my final raster file I got 12 categories rather than just 2 or one single elevation sliding scale. Once I added in the elevation raster and associated it with the Slope and Aspect, my issues with mapping the data went away.

Below is a picture of the final output of my script, as well as the mapped final data. 

Image 1: Script final output 
Image 2: Mapped final data  


Module 6 Script FlowChart



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