R: Frequency table

freq {terra} | R Documentation

## Frequency table

### Description

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

### Usage

    ## S4 method for signature 'SpatRaster'
    freq(x, digits=0, value=NULL, bylayer=TRUE, usenames=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`

### Value

`matrix` or `data.frame` with 3 columns (layer, value, count) or, if `bylayer=FALSE` two columns (value, count). If any of the layers of `x` is categorical, there is an additional column (label). A `data.frame` is returned if `usenames=TRUE` or if any of the layers of `x` is categorical.

### 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)

[Package terra version 1.4-7 Index]