Slopes for Arc Second DEMs for another area

 


This graph is for Glacier National Park.  It has a lot more elevations, so with the same number of bins it has much smoother curves than the last example.  But what is more interesting, the MICRODEM example, using the different x and y spacing, is not the same as it was in the previous example compared to using GDAL and using a data spacing that is the average of the x and y spacings.  They match below about 30% slopes, and above about 80%, but in between there are some significant differences.

Bottom line, software should adapt, and the coding is not that hard.  Most programs currently get it right.

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