terra: NAflag – R documentation

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NAflag

Set the NA flag

Description

The main purpose of this method is to allow correct reading of a SpatRaster that is based on a file that has an incorrect NA flag. The file is not changed, but flagged value is set to NA when values are read from the file ("lazy evaluation"). In contrast, if the values are in memory the change is made immediately.

To change values, it is generally better to use classify

Usage

## S4 method for signature 'SpatRaster'
NAflag(x)

## S4 replacement method for signature 'SpatRaster'
NAflag(x)<-value

Arguments

`x`	SpatRaster
`value`	numeric. The value to be interpreted as NA; set this before reading the values from the file. This can be a single value, or multiple values, one for each data source (file / subdataset)

Value

none or numeric

Examples

s <- rast(system.file("ex/logo.tif", package="terra"))[[1]]   
NAflag(s) <- 255
plot(s)
NAflag(s)

terra

Spatial Data Analysis

v1.2-10

GPL (>= 3)

Authors

Robert J. Hijmans [cre, aut] (<https://orcid.org/0000-0001-5872-2872>), Roger Bivand [ctb] (<https://orcid.org/0000-0003-2392-6140>), Karl Forner [ctb], Jeroen Ooms [ctb] (<https://orcid.org/0000-0002-4035-0289>), Edzer Pebesma [ctb] (<https://orcid.org/0000-0001-8049-7069>)

Initial release

2021-05-12