NAG Library Routine Document

E04REF

1  Purpose

2  Specification

3  Description

4  References

5  Arguments

1:     $\mathrm{HANDLE}$ – TYPE (C_PTR)Input

On entry: the handle to the problem. It needs to be initialized by E04RAF and must not be changed.

2:     $\mathrm{NVAR}$ – INTEGERInput

On entry: $n$, the number of decision variables $x$ in the problem. It must be unchanged from the value set during the initialization of the handle by E04RAF.

3:     $\mathrm{CVEC}\left(\mathbf{NVAR}\right)$ – REAL (KIND=nag_wp) arrayInput

On entry: the dense vector $c$ of the objective function.

4:     $\mathrm{IFAIL}$ – INTEGERInput/Output

On entry: IFAIL must be set to $0$, $-1\text{ or }1$. If you are unfamiliar with this argument you should refer to Section 3.4 in How to Use the NAG Library and its Documentation for details.

For environments where it might be inappropriate to halt program execution when an error is detected, the value $-1\text{ or }1$ is recommended. If the output of error messages is undesirable, then the value $1$ is recommended. Otherwise, the recommended value is $-1$. When the value $-\mathbf{1}\text{ or }1$ is used it is essential to test the value of IFAIL on exit.

On exit: $\mathbf{IFAIL}=\mathbf{0}$ unless the routine detects an error or a warning has been flagged (see Section 6).

6  Error Indicators and Warnings

$\mathbf{IFAIL}=1$

The supplied HANDLE does not define a valid handle to the data structure for the NAG optimization modelling suite. It has not been initialized by E04RAF or it has been corrupted.

$\mathbf{IFAIL}=2$

The problem cannot be modified in this phase any more, the solver has already been called.

$\mathbf{IFAIL}=3$

The objective function has already been defined.

$\mathbf{IFAIL}=4$

On entry, $\mathbf{NVAR}=〈\mathit{\text{value}}〉$, expected $\mathrm{value}=〈\mathit{\text{value}}〉$.
Constraint: NVAR must match the value given during initialization of HANDLE.

$\mathbf{IFAIL}=-99$

An unexpected error has been triggered by this routine. Please contact NAG.

See Section 3.9 in How to Use the NAG Library and its Documentation for further information.

$\mathbf{IFAIL}=-399$

Your licence key may have expired or may not have been installed correctly.

See Section 3.8 in How to Use the NAG Library and its Documentation for further information.

$\mathbf{IFAIL}=-999$

Dynamic memory allocation failed.

See Section 3.7 in How to Use the NAG Library and its Documentation for further information.

7  Accuracy

8  Parallelism and Performance

9  Further Comments

10  Example