E05 Chapter Contents
E05 Chapter Introduction
NAG Library Manual

# NAG Library Routine DocumentE05JKF

Note:  before using this routine, please read the Users' Note for your implementation to check the interpretation of bold italicised terms and other implementation-dependent details.

## 1  Purpose

E05JKF is used to get the value of an integer E05JBF optional parameter. E05JKF can be used before or after calling E05JBF, but the initialization routine E05JAF must have been called before calling E05JKF.

## 2  Specification

 SUBROUTINE E05JKF ( OPTSTR, IVALUE, COMM, LCOMM, IFAIL)
 INTEGER IVALUE, LCOMM, IFAIL REAL (KIND=nag_wp) COMM(LCOMM) CHARACTER(*) OPTSTR

## 3  Description

E05JKF obtains the current value of an integer-valued optional parameter. For example
```CALL E05JKF ('Local Searches Limit', LOCLIM, COMM, LCOMM, IFAIL)
```
will result in the value of the optional parameter Local Searches Limit being output in LOCLIM.
The default values of the optional parameters Function Evaluations Limit, Splits Limit and Static Limit depend on the problem parameter ${n}_{r}$ (the number of non-fixed variables). A default value for each of these optional parameters will be set in the first call to the solver E05JBF: before that time, getting the value of any of these optional parameters using E05JKF will not return a meaningful result.
A complete list of optional parameters, their symbolic names and default values is given in Section 11 in E05JBF.

None.

## 5  Parameters

1:     OPTSTR – CHARACTER(*)Input
On entry: a string identifying an integer-valued optional parameter (as described in Section 11 in E05JBF).
2:     IVALUE – INTEGEROutput
On exit: if ${\mathbf{IFAIL}}={\mathbf{0}}$ on exit, IVALUE contains the integer value associated with the optional parameter in OPTSTR.
3:     COMM(LCOMM) – REAL (KIND=nag_wp) arrayCommunication Array
On entry: communication data as initialized by E05JAF.
4:     LCOMM – INTEGERInput
On entry: the dimension of the array COMM as declared in the (sub)program from which E05JKF is called.
Constraint: ${\mathbf{LCOMM}}\ge 100$.
5:     IFAIL – INTEGERInput/Output
On entry: IFAIL must be set to $0$, $-1\text{​ or ​}1$. If you are unfamiliar with this parameter you should refer to Section 3.3 in the Essential Introduction 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, if you are not familiar with this parameter, the recommended value is $0$. When the value $-\mathbf{1}\text{​ or ​}\mathbf{1}$ 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

If on entry ${\mathbf{IFAIL}}={\mathbf{0}}$ or $-{\mathbf{1}}$, explanatory error messages are output on the current error message unit (as defined by X04AAF).
Errors or warnings detected by the routine:
${\mathbf{IFAIL}}=1$
 On entry, ${\mathbf{LCOMM}}<100$, or the initialization routine E05JAF has not been called.
${\mathbf{IFAIL}}=2$
The optional parameter given in OPTSTR is invalid. A keyword or keyword combination was not recognized.

Not applicable.