JuliaSwitch

JuliaSwitch is a high-level R–Julia interface. The package provides a common syntax that enables users to switch between multiple backends for R–Julia communication without changes to the code base.

• Run Julia code via a julia_*() helper function or julia_cmd_line()/julia_cmd_block();
• Push objects to Julia using julia_push();
• Pull objects back via julia_pull();

Motivation

JuliaSwitch was motivated our work on animal tracking with patter. This package provides an R interface to Patter.jl, which fit state-space models to animal-tracking data in Julia.

When patter was first developed, we used JuliaCall as a R–Julia interface. That package connects R and Julia via a C interface, which is fast but can be unstable across Julia versions and platforms. (We experienced particular challenges on Linux when using R and Julia packages that require the same dynamic libraries.)

JuliaConnectoR is another R–Julia option. Unlike JuliaCall, this package interfaces R and Julia using Transmission Control Protocol. This is a looser form of integration which trades speed for stability.

JuliaSwitch became the solution to toggle between these two options.

Installation

JuliaSwitch can be installed with:

install.packages("devtools")
devtools::install_github("edwardlavender/JuliaSwitch", 
                         dependencies = TRUE)

Functionality

• Run julia_backend("JuliaCall") or julia_backend("JuliaConnectoR") to set the Julia backend.

• Start a Julia session via julia_start().

• Run arbitrary Julia code via julia_cmd_line() and julia_cmd_block().

• For selected operations, helper functions are provided:

  • julia_pkg_activate() activates a local environment;
  • julia_pkg_add() adds packages;
  • julia_using() and julia_import() load and import packages;
  • julia_include() sources Julia scripts;
  • julia_println() prints lines;
  • julia_save() and julia_load() save and load files;

• To push objects from R to Julia, use julia_push().

• To pull objects back from Julia to R, use julia_pull().

• Stop a Julia session via julia_stop().

S3 methods

JuliaSwitch uses S3 methods to handle object transfers between R and Julia. Method dispatch is implemented by the internal functions julia_allot(), juliaAllot() and juliaTranslate().The default methods call the relevant JuliaCall or JuliaConnectoR routines. Special cases (such as data.frames and terra::SpatRasters) are handled by custom methods. Specify additional methods for other special cases.

Code of conduct

Please note that the JuliaSwitch project is released with a Contributor Code of Conduct. By contributing to this project, you agree to abide by its terms.