Compare-methods | R Documentation |
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 compare
and logic
methods implement these operators in a method that can return NA
istead of FALSE
and allows for setting an output filename.
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): ==
## S4 method for signature 'SpatRaster'
compare(x, y, oper, falseNA=FALSE, filename="", overwrite=FALSE, ...)
## S4 method for signature 'SpatRaster'
logic(x, oper, falseNA=FALSE, filename="", overwrite=FALSE, ...)
x |
SpatRaster |
y |
SpatRaster or numeric |
oper |
character. Operator name. For |
falseNA |
logical. Should the result be |
filename |
character. Output filename |
overwrite |
logical. If |
... |
additional arguments for writing files as in |
SpatRaster or SpatExtent
all.equal
, Arith-methods. See ifel
to conveniently combine operations and Math-methods
or app
to apply any R function to a SpatRaster.
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
compare(r1, r2, "==")
compare(r1, r2, "==", TRUE)
Add the following code to your website.
For more information on customizing the embed code, read Embedding Snippets.