ILOG CPLEX C++ API 9.0 Reference Manual

IloCplex::PWLFormulation
IloCplex::PWLFormulation
Category
Definition File
Include Files
Synopsis
Inner Enumeration
ilocplexi.h
ilocplex.h
PWLFormulation{
LambdaSOS,
LambdaBin,
Disjunctive,
Delta
};
Description The enumeration PWLFormulation defines symbolic constants that represent
various ways of representing piecewise linear expressions in a MIP. Which of these
ways to use is controlled by the method setPWLFormulation. All of these
formulations have the same theoretical strength. However, in practice, the effectiveness
for solving a particular model may vary dramatically, depending on the formulation
being used. These are the various formulations:
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Disjunctive, the default, represents a tight formulation of the logical disjunction
underlying the function that is being made piecewise linear.
LambdaSOS represents a transformation of a piecewise linear expression in which
a variable is created for each breakpoint, and a special ordered set of type 2 (SOS2)
is added for those variables.
LambdaBin represents a transformation of a piecewise linear expression similar to
LambdaSOS in which, however, the SOS2 constraint is replaced by a set of linear
constraints defined over additional binary variables.
Delta indicates a cumulative formulation.
Fields
LambdaSOS
LambdaBin
Disjunctive
Delta
Group optim.cplex.cpp.logical
The API of ILOG CPLEX Logical Formulations for users of C++.
Description
What Are Logical Constraints
ILOG CPLEX C++ API 9.0 REFERENCE M ANUAL 230