slope¶

slope

Slope of cells using a digital elevation model

Result = slope(dem)
dem

spatial scalar

Result

spatial scalar

Options¶

--unittrue

horizontal and vertical scale is measured in true distance; values on dem are interpreted as real heights (default).

--unitcell

horizontal and vertical scale is measured in number of cell lengths; values on dem are interpreted as number of cell lengths.

Operation¶

For each cell, calculates the slope on basis of the elevation dem of its eight nearest neighbours in a 3 x 3 cell window. The third-order finite difference method is used, proposed by Horn, also used by Skidmore. The slope on Result is given in dZ/dX, which is the increase in height (vertical direction dZ) per distance in horizontal direction (dX). This result value is often reffered to as a percentage. Thus if slope returns a value of 0.12, one says a slope value of 12 %.

Group¶

This operation belongs to the group of Derivatives of elevation maps

Examples¶

1. • pcrcalc
binding
Result = Result.map;
Dem = Dem.map;
initial
report Result = slope(Dem);

• python
 Result.map Dem.map  