Standard mathematical methods for computations with SpatRaster objects. Computations are local (applied on a cell by cell basis). If multiple SpatRaster objects are used, these must have the same extent and resolution. These have been implemented:
abs, sign, sqrt, ceiling, floor, trunc, cummax, cummin, cumprod, cumsum, log, log10, log2, log1p, acos, acosh, asin, asinh, atan, atanh, exp, expm1, cos, cosh, sin, sinh, tan, tanh, round, signif
Instead of directly calling these methods, you can also provide their name to the math method. This is useful if you want to provide an output filename.
The following methods have been implemented for SpatExtent: round, floor, ceiling
round has also been implemented for SpatVector, to round the coordinates of the geometries.
# S4 method for SpatRaster
sqrt(x)# S4 method for SpatRaster
log(x, base=exp(1))
# S4 method for SpatRaster
round(x, digits=0)
# S4 method for SpatRaster
math(x, fun, digits=0, filename="", overwrite=FALSE, ...)
# S4 method for SpatVector
round(x, digits=4)
SpatRaster
a positive or complex number: the base with respect to which logarithms are computed
Number of digits for rounding
character. Math function name
character. Output filename
logical. If TRUE, filename is overwritten
additional arguments for writing files as in writeRaster
SpatRaster or SpatExtent
See app to use mathematical functions not implemented by the package, and Arith-methods for arithmetical operations
# NOT RUN {
r1 <- rast(ncols=10, nrows=10)
v <- runif(ncell(r1))
v[10:20] <- NA
values(r1) <- v
r2 <- rast(r1)
values(r2) <- 1:ncell(r2) / ncell(r2)
r <- c(r1, r2)
s <- sqrt(r)
# same as
math(r, "sqrt")
round(s, 1)
# }
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