geodiv (version 1.1.0)

sdr: Surface Area Ratio

Description

Calculates the surface area ratio of a raster or matrix. This is the ratio of a flat surface to the actual surface.

Usage

sdr(x)

Value

A numeric value representing the surface area ratio.

Arguments

x

A raster or matrix.

Details

This function scales both x and y, as well as the surface value (z), to between 0 and 1 to best match their units. This is done because most satellite data have units where the x, y units do not equal the z units. Surface area is calculated over the sample area (N-1, M-1).

Examples

# import raster image
data(normforest)
normforest <- terra::unwrap(normforest)

# calculate the surface area ratio
Sdr <- sdr(normforest)