DESCRIPTION
r.gradient create a gradient map. It is able to create
horizontal, vertical and oblique gradient.
EXAMPLES
To calculate vertical gradient from North to South
r.gradient output=gradient_ns range=0,50 direction=N-S
To calculate horizontal gradient from East to West
r.gradient output=gradient_ea range=10,20 direction=E-W
To calculate oblique gradient from North-East to South-West you have to
set also the percentile option to set the slope of the gradient.
r.gradient output=gradient_oblique range=10,20 direction=NE-SW
AUTHOR
Luca Delucchi, Fondazione E. Mach (Italy)
Thanks to Johannes Radinger for the code of horizontal and vertical gradient
Last changed: $Date$