CPXqpindefcertificate

int CPXPUBLIC CPXqpindefcertificate(CPXCENVptr env, CPXCLPptr lp, double * x)

Definition file: cplex.h

Include files: cplex.h

The routine CPXqpindefcertificate computes a vector x that satisfies the inequality x'Qx < 0 . Such a vector demonstrates that the Q matrix violates the assumption of positive semi-definiteness, and can be an aid in debugging a user's program if indefiniteness is an unexpected outcome.

Example

 status = CPXqpindefcertificate (env, lp, x);

Parameters:

env	A pointer to the CPLEX environment as returned by `CPXopenCPLEX`.
lp	A pointer to a CPLEX problem object as returned by `CPXcreateprob`.
x	An array to receive the values of the vector that is to be returned. The length of this array must be the same as the number of quadratic variables in the problem, which can be obtained by calling `CPXgetnumquad` for example.

Returns:

The routine returns zero on success and nonzero if an error occurs.