I need to run a integer quadratic program - preferably using free/open source tools - and have settled on using Ipopt with pyomo.
I'm using Windows 10, and have found installation of ipopt difficult, but it seems that using anaconda is the simplest way.
I've installed ipopt with
conda install -c conda-forge ipopt which seems to have worked.
However, running a small optimization problem (see below) raises:
The code execution cannot proceed because cyggcc_s-1.dll was not found. Reinstalling the program may fix this problem.
The code execution cannot proceed because cyggfortran-3.dll was not found. Reinstalling the program may fix this problem.
The problem I am running is
from pyomo.environ import *
m = ConcreteModel()
m.x = Var()
m.c = Constraint(expr=m.x >= 2)
m.o = Objective(expr=m.x)
s = SolverFactory('ipopt')
s.options['fixed_variable_treatment'] = 'make_parameter'
s.solve(m, tee=True, keepfiles=True)
There are various guides for installing ipopt on Windows, but nothing I've found authoritative. I've seen reference to needing to install Intel Fortran compilers, but haven't found where to get these, and am wondering if that's my problem.