|
Some options (relief, openness) require that
a region size be selected. The size is in meters, and converted into the
number of grid points needed. 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
slope algorithm
- All slope/aspect
- Slope (%) (100 * tan)
- Slope (%) and components (x and y)
- Degrees
- m/m
- Sin
- log10 tangent
- ln tangent
- sqrt sin
- slope and roughness
- Roughness (std of slope)
- Roughness (from SSO)
- Slope error estimator
- Aspect--uses current
slope algorithm
- Aspect 360
- N-S component: sin(aspect), 1 is east, -1 is west
- E-W component: cos(aspect), 1 is north, -1 is south
- Curvature: They will be
drawn with a percentile color stretch. The five at once will be
threaded and probably execute faster than a single layer.
- All 5 curvatures, Evans algorithm
- Profile/slope convexity
- Plan convexity
- Cross sectional curvature
- Minimum curvature
- Maximum curvature
- 5 algorithms, 2 curvatures
- Relief
- Relief, average elevation, elevation standard deviation, REL
(percentage of area that is lower), and TPI: all for a specified region
size
- Relief, Summit levels, Base Level,
Geophysical Relief
- Immediate neighborhood drop: drop off is the distance from the point to the
lowest point in the box with the selected size.
- Rugosity
- Convergence index
- Topographic ruggedness index
and topographic position index (TPI amd TRI)
- Openness
- Reflectance
- Terrain category: pick a terrain category,
and the points meeting the criteria will have a single value in the
resulting grid.
- 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
direction, Roughness
factor (slope)
- 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
|
Data
Manipulation, Resample, DEM format,
convert to Geotiff, which allows conversion of all DEMs in a directory.