Send the solver's progress log to a file

Adds a log_file attribute to a JuMP/HiGHS solver option set, so the solver writes its iteration log where it can be watched and kept.

Usage

with_solver_log(opts, file = "highs.log")

Arguments

opts

a solver option set, e.g. solver_options$julia_highs_barrier.

file

log file name. A bare name is written into the run's solver/ directory; an absolute path is used as given.

Value

opts with the attribute appended to its inc3 block.

Details

The log lands in the run's solver/ directory, alongside the generated model, so it can be followed while the solve runs:

tail -f <scenario>/runs/<solve>/solver/highs.log

Without it, HiGHS logs to stdout, which a piped R session buffers – the output appears only when the process ends, and nothing is retained.

See also

solver_options (the shipped solver option sets)

Other interpolation: interpolate_model(), subset_model_regions()

Examples

if (FALSE) { # \dontrun{
# barrier, with a followable log
opt <- with_solver_log(solver_options$julia_highs_barrier)
scen <- write_script(scen, solver = opt)
} # }