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How do I generate grid square polygons from a 5m DTM file?


For my dissertation I have collected point features as coordinates and want to relate their distribution around a lake to elevation to see if there is any pattern/relationship between them.

I have downloaded the 5m DTM file for the location but want to be able to automatically calculate the number of points within each grid square of the DTM but I'm unsure how to do this.

I then want to be able to create graphs from this data of elevation vs. number of points.

As a relative newbie to GIS, I don't have much experience doing what appear to me, to be more complicated processes.

I'm using ArcMap 10.2.2 and I believe I have access to all toolbox functions whether on my laptop or a university computer!


To clarify, you want to know the number of points that coincide with each cell of the 5 m DTM? If so, I'd try:

  1. convert the DTM to polygon using the raster to feature tool
  2. Perform a join-by-location of the polygon feature to the points. Now each point will be labelled with the ID of the polygon cell it resides in.
  3. Create a histogram of the polygon cell IDs in the point featureclass. This reveals how many points are located in each polygon cell.

Let me know if this is what you're looking for.


To pass values from the raster to a point file, use the Spatial Analyst tool, Extract Values to Points.

/r/gis


Watch the video: How to create DEM in ArcMap (September 2021).