Tool Maximum Flow Path Length
This tool calculates the maximum upstream or downstream distance or weighted distance along the flow path for each cell based on 'Deterministic 8 (D8)' (O'Callaghan and Mark 1984) flow directions.
References
- O'Callaghan, J.F. & Mark, D.M. (1984): The extraction of drainage networks from digital elevation data. Computer Vision, Graphics and Image Processing, 28:323-344. doi:10.1016/S0734-189X(84)80011-0.
 
- Author: O.Conrad (c) 2016
 
- Menu: Terrain Analysis|Hydrology|Flow Accumulation
 
Parameters
|   | Name | Type | Identifier | Description | Constraints | 
| Input | Elevation | grid, input | ELEVATION | - | - | 
 | Weights (*) | grid, input, optional | WEIGHTS | - | - | 
| Output | Flow Path Length | grid, output | DISTANCE | - | - | 
| Options | Grid System | grid system | PARAMETERS_GRID_SYSTEM | - | - | 
 | Direction of Measurement | choice | DIRECTION | - | Available Choices: [0] downstream [1] upstream Default: 0 | 
| (*) optional | 
Command-line
Usage: saga_cmd ta_hydrology 27 [-ELEVATION <str>] [-WEIGHTS <str>] [-DISTANCE <str>] [-DIRECTION <str>]
  -ELEVATION:<str>	Elevation
	grid, input
  -WEIGHTS:<str>  	Weights
	grid, input, optional
  -DISTANCE:<str> 	Flow Path Length
	grid, output
  -DIRECTION:<str>	Direction of Measurement
	choice
	Available Choices:
	[0] downstream
	[1] upstream
	Default: 0