gurobi_iis()


gurobi_iis()

gurobi_iis ( model, params )

Computes an IIS

Arguments:

model: The model struct must contain a valid Gurobi model. See the gurobi function for a description of model's required fields and values.

params: The params struct may contain Gurobi parameters. See the gurobi function for a description of the param's fields and values.

Example usage:

clear model params
model = gurobi_read('examples/data/klein1.mps')
params.resultfile = 'myiis.ilp';
iis   = gurobi_iis(model, params);\

The IIS result

The gurobi_iis function returns a struct iis, with various results stored in its named components. The specific results that are available depend on the type of model.

The iis struct will always contain the following fields

minimal
A logical scalar that indicates whether the computed IIS is minimal. It will normally be true, but it may be false if the IIS computation was stopped early (e.g due to a time limit or a user interrupt).
constrs
A logical vector that indicates whether a linear constraint appears in the computed IIS.
lb
A logical vector that indicates whether a lower bound in the computed IIS.
ub
A logical vector that indicates whether a upper bound appears in the computed IIS.

If your model contains SOS constraints the IIS struct will contain the following field:

sos
A logical vector that indicates whether an sos constraint appears in the computed IIS

If your model contains cones or quadratic constraints the IIS struct will contain the following field:

qconstrs
A logical vector that indicates whether the cone or quadratic constraint appears in the computed IIS. Note that any cones in the model will appear first in this vector, followed by the quadratic constraints.