Compare-methods.Rd
These methods compare the location and resolution of Raster* objects. That is, they compare their spatial extent, projection, and number of rows and columns.
For BasicRaster
objects you can use ==
and !=
, the values returned is a single logical value TRUE
or FALSE
For RasterLayer objects, these operators also compare the values associated with the objects, and the result is a RasterLayer object with logical (Boolean) values.
The following methods have been implemented for RasterLayer objects:
==, !=, >, <, <=, >=
A logical value or a RasterLayer object, and in some cases the side effect of a new file on disk.
r1 <- raster()
r1 <- setValues(r1, round(10 * runif(ncell(r1))))
r2 <- setValues(r1, round(10 * runif(ncell(r1))))
as(r1, 'BasicRaster') == as(r2, 'BasicRaster')
#> [1] TRUE
r3 <- r1 == r2
b <- extent(0, 360, 0, 180)
r4 <- setExtent(r2, b)
as(r2, 'BasicRaster') != as(r4, 'BasicRaster')
#> [1] TRUE
# The following would give an error. You cannot compare RasterLayer
# that do not have the same BasicRaster properties.
#r3 <- r1 > r4