Module Gradient Vector from Cartesian to Polar Coordinates
Converts gradient vector from directional components (Cartesian) to polar coordinates (direction or aspect angle and length or tangens of slope).
The module supports three conventions on how to measure and output the angle of direction:
(a) mathematical: direction angle is zero in East direction and the angle increases counterclockwise
(b) geographical: direction angle is zero in North direction and the angle increases clockwise
(c) zero direction and orientation are user defined
- Author: Victor Olaya & Volker Wichmann (c) 2004-2010
- Specification: grid
- Menu: Grid|Calculus|Conversions
Parameters
| | Name | Type | Identifier | Description | Constraints |
|---|
| Input | X Component | Grid (input) | DX | - | - |
| Y Component | Grid (input) | DY | - | - |
| Output | Direction | Grid (output) | DIR | - | - |
| Length | Grid (output) | LEN | - | - |
| Options | Polar Angle Units | Choice | UNITS | - | Available Choices:
[0] radians
[1] degree
Default: 0 |
| Polar Coordinate System | Choice | SYSTEM | - | Available Choices:
[0] mathematical
[1] geographical
[2] user defined
Default: 1 |
| User defined Zero Direction | Floating point | SYSTEM_ZERO | given in degree clockwise from North direction | Minimum: 0.000000
Maximum: 360.000000
Default: 0.000000 |
| User defined Orientation | Choice | SYSTEM_ORIENT | - | Available Choices:
[0] clockwise
[1] counterclockwise
Default: 0 |
Command-line
Usage: saga_cmd grid_calculus 15 [-DX <str>] [-DY <str>] [-DIR <str>] [-LEN <str>] [-UNITS <str>] [-SYSTEM <str>] [-SYSTEM_ZERO <str>] [-SYSTEM_ORIENT <str>]
-DX:<str> X Component
Grid (input)
-DY:<str> Y Component
Grid (input)
-DIR:<str> Direction
Grid (output)
-LEN:<str> Length
Grid (output)
-UNITS:<str> Polar Angle Units
Choice
Available Choices:
[0] radians
[1] degree
Default: 0
-SYSTEM:<str> Polar Coordinate System
Choice
Available Choices:
[0] mathematical
[1] geographical
[2] user defined
Default: 1
-SYSTEM_ZERO:<str> User defined Zero Direction
Floating point
Minimum: 0.000000
Maximum: 360.000000
Default: 0.000000
-SYSTEM_ORIENT:<str> User defined Orientation
Choice
Available Choices:
[0] clockwise
[1] counterclockwise
Default: 0