The Drainage Network Extraction operation can be directly executed by typing one of the following expressions on the command line of the Main window:
|
OUTMAP |
= |
MapDrainageNetworkExtraction(flowacc_rasmap, threshold) |
|
OUTMAP |
= |
MapDrainageNetworkExtraction(flowacc_rasmap, threshold_rasmap, flowdir_rasmap) |
where:
|
OUTMAP |
is the name of the output raster map. |
|
MapDrainageNetworkExtraction |
|
|
is the command to start the Drainage Network Extraction operation. |
|
|
flowacc_rasmap |
is a raster map that is the outcome of the Flow Accumulation operation, i.e. a raster map with a value domain. |
|
threshold |
a value (integer > 0) to define the minimum number of pixels (i.e. the contributing area) that should drain into the pixel examined to form a network channel. If the condition is met, true is assigned in the output map; else false is assigned. |
|
threshold_rasmap |
is a raster map where the pixel values define the minimum number of pixels (i.e. the contributing area) that should drain into the pixel examined to form a network channel. |
|
flowdir_rasmap |
is a raster that is the outcome of the Flow Direction operation, i.e. a raster map with system domain FlowDirection. |
When the definition symbol = is used, a dependent output map is created; when the assignment symbol := is used, the dependency link is immediately broken after the output map has been calculated.
The output map will always use system domain Bool.
See also:
Drainage network extraction : functionality