Calling R From Julia

Julia’s younger ecosystem sometimes lacks packages for specialized tasks. The solution: leverage R packages directly from Julia through RCall.jl, enabling seamless interoperability between the two languages.

Installation

] add RCall

Running R Code from Julia

Interactive Mode (REPL)

After importing RCall, access the R REPL by typing $. The prompt switches from julia> to R>, allowing native R commands:

julia> using RCall

# type `$` to enter R mode

R> install.packages("ggplot2")

R> library(ggplot2)

R> data(diamonds)

R> ggplot(diamonds, aes(x=carat, y=price)) + geom_point()

Non-Interactive Mode

The @R_str macro executes R code programmatically:

julia> R"y = 2"
RObject{RealSxp}
[1] 2

Sending Julia Variables to R

Using `@rput`

julia> x = 1
1

julia> @rput x
1

R> x
[1] 1

String Interpolation

julia> x = 1
1

julia> R"y = $x"
RObject{IntSxp}
[1] 1

R> 1 + $x
[1] 2

Retrieving R Variables in Julia

Using `@rget`

julia> R"z = 5"
RObject{RealSxp}
[1] 5

julia> @rget z
5.0

julia> z
5.0

Using `rcopy()`

julia> robj = R"z"
RObject{RealSxp}
[1] 5

julia> rcopy(robj)
5.0