Accessing QCP problem data
These routines and methods access information about quadratically constrained problems (QCPs).
These routines and methods access information about quadratically constrained problems (QCPs). Second order cone programming (SOCP) problems are treated as a special case of QCP. For more about that idea, see Solving problems with quadratic constraints (QCP) in the CPLEX User's Manual. Problem query routines and methods access information about a problem object after it has been created. They can be used at any time, even after problem modifications.
Names of classes, methods, and symbolic constants in the C#.NET API correspond very closely to those in the Java API with these systematic exceptions:
-
In the Java API, the names of classes begin with the prefix Ilo, whereas in C#.NET they do not.
-
In the Java API, the names of methods conventionally begin with a lowercase letter, for example,
addCols, whereas in the C#.NET API, the names of methods conventionally begin with an uppercase (that is, capital) letter, for example,AddColsaccording to Microsoft practice.
| Purpose | Java API | C++ API | C API |
|---|---|---|---|
| Accesses number of quadratic constraints in a model | IloCplex.getNQCs() | IloCplex:: getNQCs |
CPXXgetnumqconstrs and CPXgetnumqconstrs
|
| Accesses the index of a quadratic constraint in a model if given the name of the constraint | IloLPMatrix.getIndex(ilog.concert.IloRange) (no difference between linear and quadratic constraints in this respect) | ---- |
CPXXgetqconstrindex and CPXgetqconstrindex
|
| Accesses a specified quadratic constraint in a model |
IloLPMatrix.getRows(int, int, double[], double[], int[][], double[][])
or
IloRange.getExpr() (no difference between linear and quadratic constraints in this respect) |
IloRange:: getExpr (no difference between linear and quadratic constraints in this respect) |
CPXXgetqconstr and CPXgetqconstr
|
| Accesses the name of a specified quadratic constraint in a model | IloRange.getName(). IloRange inherits this method from the interface IloAddable.getName() (no difference between linear and quadratic constraints in this respect) | IloRange:: getName IloRange inherits this method from the class IloExtractable via the class IloConstraint. (no difference between linear and quadratic constraints in this respect) |
CPXXgetqconstrname and CPXgetqconstrname
|
| Accesses the slack values of a range of quadratic constraints in a model | IloCplex.getSlack(ilog.concert.IloRange) | IloCplex:: getSlack |
CPXXgetqconstrslack and CPXgetqconstrslack
|
| Accesses the activity levels of a range of quadratic constraints in a model | IloCplex.getAX(ilog.concert.IloLPMatrix) (no difference between linear and quadratic constraints in this respect) | IloCplex:: getAX (no difference between linear and quadratic constraints in this respect) |
CPXXgetxqxax and CPXgetxqxax
|