A file-based Julia wrapper for the PaPILO library for presolving linear and mixed-integer linear optimization problems.
using PaPILO
# 1) presolve problem from file
PaPILO.presolve_write_from_file(
input_instance, # original MPS file
postsolve_file, # file name where to write the postsolve information
presolved_instance # file name where to write the presolved problem
)
# 2) solve problem from presolved_instance with an external solver
# write solution to file reduced_sol
# 3) postsolve: compute the solution in the original problem space from
# the solution in the reduced space
PaPILO.postsolve_from_file(
postsolve_file, # postsolve file produced by the previous function
reduced_sol, # .sol file of a solution that is feasible for the reduced problem
original_sol, # file name where to write the solution to the original problem
)