Part B of the lab was also a Boolean suitability analysis but used raster layers instead. Instead of creating river and highway buffers we used the Euclidean Distance tool to obtain a raster of the distance from the rivers and highways. To "combine" the four criteria rasters we used the Raster Calculator to create an expression that would show the cells in the raster that met all four criteria. Using this calculator made me revert back to my binary number knowledge and really understand what I wanted the expression to do. We also used the Combine tool on all four Boolean rasters. Using the attribute table one could then search for rows where all four criteria were met (=1).
Our final step in the assignment, Part C, required us to use weighted overlays to analyze the suitability of land based on the provided criteria layers. The first run of the tool required us to weight each criteria layer equally. The second run of the tool required us to weight the criteria layers differently. My final map is a comparison of the two weighted overlays.
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| Suitability Analysis Using Weighted Overlay |
This lab was a review of previously acquired geoprocessing skills and new tools were introduced as well (Weighted Overlay, Raster to Polygon and Polygon to Raster Conversion, Raster Calculator, Combine). I also noticed that all provided layers were not in the same projection. I used the Project Raster and the Project tools to reproject layers as needed. I also had to refresh my memory about using the Field Calculator and calculating area for raster layers as well as looking at the provided Statistics for a field column. After reclassifying layers to Boolean criteria, I found it helpful to add a Description text field to help keep track of what the Boolean values represented.
This added field was useful after performing Unions and Selection Queries and kept me from getting criteria confused.
