terra (version 0.6-9)

math: Arithmetic, logical and general mathematical methods

Description

Standard operators and 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:

Arith: +, -, *, /, ^, %%, %/%

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

The terra package does not distunguish between NA (not available) and NaN (not a number) and that both are represented as NaN.

Logical: !, &, |

Summary: "max", "min", "range", "prod", "sum", "any", "all"

Math: "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"

For SpatExtent the following methods have been implemented: "round", "floor", "ceil", "=="

Usage

# S4 method for SpatRaster
is.na(x)

Arguments

x

SpatRaster

Value

SpatRaster

seealso

ifel to convieniently combine operations and app to use mathematical functions not implemented by the package.

Examples

# 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)
r3 <- r1 + r2
r2 <- r1 / 10
r3 <- r1 * (r2 - 1 / r2)


b <- c(r1, r2, r3)
b2 <- b * 10
s <- sqrt(b2)
round(s, 1)

max(s)
max(s, na.rm=TRUE)

x <- is.na(s)

y <- which.max(s)
# }