metrics_dispersion: Dispersion metrics

In ptompalski/lidRmetrics: Point cloud metrics for the lidR package.

Dispersion metrics

Description

Metrics characterizing the dispersion of point heights

Usage

metrics_dispersion(z, dz = 1, zmin = NA, zmax = NA)

.metrics_dispersion

Arguments

z	Z coordinate of the point cloud (point heights)
dz	Numeric. Layer thickness to use when calculating entropy and VCI.
zmin	numeric. Minimum z value. If set, z values (heights) below are ignored in calculations.
zmax	Numeric. Maximum elevation for an entropy normalized to zmax.

Format

An object of class formula of length 2.

Details

When calculating zentropy and VCI, z values below 0 are removed.

Value

A list. Calculated metrics include:

• ziqr interquartile distance

• zMADmean mean absolute deviation (MAD) around the mean

• zMADmedian mean absolute deviation (MAD) around the median

• CRR canopy relief ratio

• zentropy entropy

• VCI vertical complexity index. Optional - calculated only if the zmax parameter is provided.

Examples

library(lidR)
library(lidRmetrics)
LASfile <- system.file("extdata", "Megaplot.laz", package="lidR")
las <- readLAS(LASfile, select = "*", filter = "-keep_random_fraction 0.5")

m1 <- cloud_metrics(las, ~metrics_dispersion(z = Z))

m2 <- pixel_metrics(las, ~metrics_dispersion(z = Z, dz = 2, zmax = 30), res = 20)

ptompalski/lidRmetrics documentation built on May 7, 2024, 2:58 p.m.