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terra (version 1.7-3)

Compare-methods: Compare and logical methods

Description

Standard comparison and logical operators for computations with SpatRasters. Computations are local (applied on a cell by cell basis). If multiple SpatRaster objects are used, these must have the same geometry (extent and resolution). These operators have been implemented:

Logical: !, &, |, isTRUE, isFALSE

Compare: ==, !=, >, <, <=, >=, is.na, is.nan, is.finite, is.infinite

See not.na for the inverse of is.na, and noNA to detect cells with missing value across layers.

The terra package does not distinguish between NA (not available) and NaN (not a number). In most cases this state is represented by NaN.

If you use a SpatRaster with a vector of multiple numbers, each element in the vector is considered a layer (with a constant value). If you use a SpatRaster with a matrix, the number of columns of the matrix must match the number of layers of the SpatRaster. The rows are used to match the cells. That is, if there are two rows, these match cells 1 and 2, and they are recycled to 3 and 4, etc.

The following method has been implemented for (SpatExtent, SpatExtent): ==

Arguments

Value

SpatRaster or SpatExtent

See Also

all.equal, Arith-methods. See ifel to conveniently combine operations and Math-methods or app to apply any R function to a SpatRaster.

Examples

Run this code
r1 <- rast(ncols=10, nrows=10)
values(r1) <- runif(ncell(r1))
r1[10:20] <- NA
r2 <- rast(r1)
values(r2) <- 1:ncell(r2) / ncell(r2)

x <- is.na(r1)
!x
r1 == r2 

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