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rapsimng package is designed to modify and run the *.apsimx simulations using R in APSIM Next Generation.


  • Find elements in the *.apsimx file


Install from CRAN.


Install the developing version from Github.


Read APSIMX file

The wheat.apsimx in the validation dataset of APSIM NG is used as an example. Function read_apsimx is used to read *.apsimx file through jsonlite::read_json and returns as a list.

# Read Wheat.apsimx file with `read_apsimx` which returns a list of json results.
file <- system.file("extdata/wheat.apsimx", package = "rapsimng")
m <- read_apsimx(file)

Search by of APSIM NG

A node in the apsimx file can be found using the path specification in APSIM NG.

potential <- search_path(m,
    path = '[Structure].BranchingRate.PotentialBranchingRate.Vegetative.PotentialBranchingRate')

Modify a found model

new_model <- potential$node
new_model$XProperty <- 'NewVariable'

Replace the new model

new <- replace_model(m, potential$path, new_model)

Save into a new apsimx file

write_apsimx(new, tempfile(fileext = '.json'))

Run apsimx file

A function run_models is wrapped for APSIM NG Models.exe in the command line and can be called to run apsimx files. See APSIM website for documentation.