Add _converttofixed for Gurobi

Author: metab0t

include/pyoptinterface/gurobi_model.hpp

@@ -66,7 +66,8 @@
 	B(GRBemptyenv);           \
 	B(GRBloadenv);            \
 	B(GRBfreeenv);            \
-	B(GRBstartenv);
+	B(GRBstartenv);           \
+	B(GRBconverttofixed);
 
 namespace gurobi
 {
@@ -251,6 +252,9 @@ class GurobiModel
 	double get_objective_coefficient(const VariableIndex &variable);
 	void set_objective_coefficient(const VariableIndex &variable, double value);
 
+	// Gurobi-specific convertofixed
+	void _converttofixed();
+
 	// Non-exported functions
 	void check_error(int error);
 

lib/gurobi_model.cpp

@@ -950,6 +950,12 @@ void GurobiModel::set_objective_coefficient(const VariableIndex &variable, doubl
 	set_variable_raw_attribute_double(variable, GRB_DBL_ATTR_OBJ, value);
 }
 
+void GurobiModel::_converttofixed()
+{
+	int error = gurobi::GRBconverttofixed(m_model.get());
+	check_error(error);
+}
+
 int GurobiModel::_constraint_index(const ConstraintIndex &constraint)
 {
 	_update_for_constraint_index(constraint.type);

lib/gurobi_model_ext.cpp

@@ -203,6 +203,8 @@ NB_MODULE(gurobi_model_ext, m)
 		BIND_F(set_normalized_coefficient)
 		BIND_F(get_objective_coefficient)
 		BIND_F(set_objective_coefficient)
+
+		BIND_F(_converttofixed)
 	    // clang-format on
 	    ;
 }