Invokes popup menu, which can be selected in
This will create a new grid, with the same size and spacing as the original
You must save the new grids (File, Save DEM)
if you want to use them again. The derivative grid can be manipulated in its own right.
Some options (relief, openness) require that
a region size be selected. The computations will use a
square centered on the point.
Some options (e.g. slope, reflectance, aspect) can be
selected from the display option of the DEM display, but
have limited modification capability since they are just
display modes of the DEM.
- Multiple parameters--This allows creation of
multiple grids while you do something else. Parameters within
each grouping are computed together, and doing more than adds little
time, but will increase memory usage.
- Slope--uses current
- Percent (100 * tan)
- log10 tangent
- ln tangent
- sqrt sine
- Curvature: create 5
different curvature grids, or all five at once. They will be
drawn with a percentile color stretch. The five at once will be
threaded and probably execute faster than a single layer.
- Relief, average elevation, elevation standard deviation, REL
(percentage of area that is lower), and TPI: all for a specified region
- Relief, Summit levels, Base Level,
- Immediate neighborhood drop: drop off is the distance from the point to the
lowest point in the box with the selected size.
- Convergence index
- Topographic ruggedness index
- Terrain category: pick a terrain category,
and the points meeting the criteria will have a single value in the
- Transform elevations
- Terrain classification--uses current classification algorithm
- Ridges--all peaks and ridges will have the
elevation; other points will be missing
- Valleys--all streams will have the elevation;
other points will be missing
- All terrain categories--will have an integer
code for the category
- Iwashashi and Pike Classification
- Terrain organization maps: Organization (s2/s3), Flatness (s1s2,
inverse slope), Fabric
- Moments for region (elevation, slope, two curvatures, the
moments for a selected region size)
- Point density: divides value at each grid point by size
of the grid; the result will in count/m².
- Optimal viewshed location
- Vegetation obstacle
grid. Will have the same size and
spacing as the DEM. Done from:
- NLCD grid--NLCD 2001
- NLCD grid--NLCD-1992
- Landfire grid
Last revision 2/1/2016