JuliaCall Update: Automated Julia Installation for R Packages


Some sneakily cool features made it into the JuliaCall v0.17.2 CRAN release. With the latest version there is now an install_julia function for automatically installing Julia. This makes Julia a great high performance back end for R packages. For example, the following is an example from the diffeqr package that will work, even without Julia installed:

install.packages("diffeqr")
library(diffeqr)
de <- diffeqr::diffeq_setup()
 
lorenz <- function (u,p,t){
  du1 = p[1]*(u[2]-u[1])
  du2 = u[1]*(p[2]-u[3]) - u[2]
  du3 = u[1]*u[2] - p[3]*u[3]
  c(du1,du2,du3)
}
u0 <- c(1.0,1.0,1.0)
tspan <- c(0.0,100.0)
p <- c(10.0,28.0,8/3)
prob <- de$ODEProblem(lorenz,u0,tspan,p)
fastprob <- diffeqr::jitoptimize_ode(de,prob)
sol <- de$solve(fastprob,de$Tsit5(),saveat=0.01)

Under the hood it’s using the DifferentialEquations.jl package and the SciML stack, but it’s abstracted from users so much that Julia is essentially an alternative to Rcpp with easier interactive development. The following example really brings the seamless integration home:

install.packages(diffeqr)
library(diffeqr)
de <- diffeqr::diffeq_setup()
degpu <- diffeqr::diffeqgpu_setup()
 
lorenz <- function (u,p,t){
  du1 = p[1]*(u[2]-u[1])
  du2 = u[1]*(p[2]-u[3]) - u[2]
  du3 = u[1]*u[2] - p[3]*u[3]
  c(du1,du2,du3)
}
u0 <- c(1.0,1.0,1.0)
tspan <- c(0.0,100.0)
p <- c(10.0,28.0,8/3)
prob <- de$ODEProblem(lorenz,u0,tspan,p)
fastprob <- diffeqr::jitoptimize_ode(de,prob)
 
prob_func <- function (prob,i,rep){
  de$remake(prob,u0=runif(3)*u0,p=runif(3)*p)
}
ensembleprob = de$EnsembleProblem(fastprob, prob_func = prob_func, safetycopy=FALSE)
sol <- de$solve(ensembleprob,de$Tsit5(),degpu$EnsembleGPUArray(),trajectories=10000,saveat=0.01)

This example does the following:

  1. Automatically installs Julia
  2. Automatically installs DifferentialEquations.jl
  3. Automatically installs CUDA (via CUDA.jl)
  4. Automatically installs ModelingToolkit.jl and DiffEqGPU.jl
  5. JIT transpiles the R function to Julia via ModelingToolkit
  6. Uses KernelAbstractions (in DiffEqGPU) to generate a CUDA kernel from the Julia code
  7. Solves the ODE 10,000 times with different parameters 350x over deSolve

What a complicated code! Well maybe it would shock you to know that the source code for the diffeqr package is only 150 lines of code. Of course, it’s powered by a lot of Julia magic in the backend, and so can your next package. For more details, see the big long post about differential equation solving in R with Julia.

4 thoughts on “JuliaCall Update: Automated Julia Installation for R Packages

  1. Looks like this may have gone away? For more details see https://github.com/SciML/diffeqr/issues/33


  2. David Katz

    says:

    Sure, I will do that.


  3. David Katz

    says:

    Tried your sample code in Windows 10 but got errors. Any help appreciated.

    R version 4.0.3 (2020-10-10) — “Bunny-Wunnies Freak Out”
    Copyright (C) 2020 The R Foundation for Statistical Computing
    Platform: x86_64-w64-mingw32/x64 (64-bit)

    Errors:
    package ‘JuliaCall’ successfully unpacked and MD5 sums checked
    package ‘diffeqr’ successfully unpacked and MD5 sums checked

    The downloaded binary packages are in
    C:\Users\dkatz\AppData\Local\Temp\RtmpyuuAyP\downloaded_packages
    > library(diffeqr)
    > de


Write a Reply or Comment

Your email address will not be published. Required fields are marked *


*

This site uses Akismet to reduce spam. Learn how your comment data is processed.