M. Deriving Roughness with ToPCAT


This exercise shows how GCD can be used for coming up with statistical models of error. We will cover coincident point analysis, interpolation error, and using the ToPCAT algorithm to look at statistics from high resolution point clouds within a user-defined moving voxel. 

Data and Materials for Exercises


Prerequisite for this Exercise

  • Some ArcGIS experience
  • ArcGIS 10.X w/ Spatial Analyst Extension
  • GCD Add-In

Step by Step

Run ToPCAT to get Roughness Surface (Simple)

Run ToPCAT as Associated Surface to Get Roughness

Exercise M - Part 3: Use Associated Surface Panel to Create Roughness


1. Start new ArcMap Document
2. Open GCD Project  ToPCATRoughnessTLSFlume.gcd
3. For each DEM in GCD Project Select Add Associated Surface and from this menu choose to Calculate a Roughness Raster.
4. Use the *.pts file associated with each flume run as input to the Generate Surface Roughness Raster dialog.
5. Due to scale of flume data you may want to adjust symbology.

ToPCAT Roughness - Exercise Part 3

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