freq: Frequency table

In terra: Spatial Data Analysis

Frequency table

Description

Frequency table of the values of a SpatRaster. NAs are not counted unless value=NA.

You can provide a SpatVector or additional SpatRaster to define zones for which to do tabulations.

Usage

## S4 method for signature 'SpatRaster'
freq(x, digits=0, value=NULL, bylayer=TRUE, usenames=FALSE, zones=NULL, wide=FALSE)

Arguments

x	SpatRaster
digits	integer. Used for rounding the values before tabulation. Ignored if NA
value	numeric. An optional single value to only count the number of cells with that value. This value can be NA
bylayer	logical. If TRUE tabulation is done by layer
usenames	logical. If TRUE layers are identified by their names instead of their numbers Only relevant if bylayer is TRUE
zones	SpatRaster or SpatVector to define zones for which the tabulation should be done
wide	logical. Should the results by "wide" instead of "long"?

Value

A data.frame with 3 columns (layer, value, count) unless bylayer=FALSE in which case adata.frame with two columns is returned (value, count).

Examples

r <- rast(nrows=10, ncols=10)
set.seed(2)
values(r) <- sample(5, ncell(r), replace=TRUE)

freq(r)

x <- c(r, r/3)
freq(x, bylayer=FALSE)
freq(x)

freq(x, digits=1)
freq(x, digits=-1)

freq(x, value=5)

terra documentation built on April 12, 2025, 1:43 a.m.