Macro ILOCOMPARATOR0

The ILOCOMPARATORi macros can be used to generate comparators over arbitrary objects.

The macros take four mandatory parameters which are:

• The name of the comparator to generate
• The type of the objects to compare
• The name of the first object to compare
• The name of the second object to compare

After this, depending on the macro used, optional parameters can be provided as argument pairs of type and name.

The body of the macro must return a Boolean value (IloBool) which is IloTrue if the comparator's left-hand side is better than its right-hand side.

Using ILOCOMPARATORi

For example, the following code defines a comparator that compares the value of two IlcFloatVar variables (provided the variables are bound):

 ILOCOMPARATOR0(CompareGreaterThan, IlcFloatVar, v1, v2) {
   return v1.getValue() > v2.getValue();
 }

This comparator can be invoked as follows:

 IloComparator<IlcFloatVar> cmp = CompareGreaterThan(getSolver());
 IloBool value = cmp(var1, var2);

Using ILOCTXCOMPARATORi

The macro ILOCTXCOMPARATORi can be used to handle a user-given context (name nu and type tu) at comparison time. The following comparator uses a contextual tolerance factor:

 ILOCTXCOMPARATOR0(CompareGreaterThanWithTolerance,IlcFloatVar, v1, v2, IlcFloat, tolerance) {
   return (v1.getValue() - v2.getValue() > tolerance);
 }

This comparator can be invoked as follows:

 IloComparator<IlcFloatVar> cmp = CompareGreaterThanWithTolerance(getSolver());
 IlcFloat tolerance = 0.8;
 IloBool value = cmp(var1, var2, (IloAny)&tolerance);

For more information, see Selectors.