e05jff may be used to supply individual integer optional parameters to e05jbf. The initialization routine e05jaf must have been called before calling e05jff.

2 Specification

Fortran Interface

Subroutine e05jff (

optstr, ivalue, comm, lcomm, ifail)

Integer, Intent (In)	::	ivalue, lcomm
Integer, Intent (Inout)	::	ifail
Real (Kind=nag_wp), Intent (Inout)	::	comm(lcomm)
Character (*), Intent (In)	::	optstr

C Header Interface

#include <nag.h>

void	e05jff_ (const char optstr, const Integer ivalue, double comm[], const Integer lcomm, Integer ifail, const Charlen length_optstr)

The routine may be called by the names e05jff or nagf_glopt_bnd_mcs_optset_int.

3 Description

e05jff may be used to supply values for integer optional parameters to e05jbf. It is only necessary to call e05jff for those arguments whose values are to be different from their default values. One call to e05jff sets one argument value.

Each integer optional parameter is defined by a single character string in optstr and the corresponding value in ivalue. For example, the following allows the function evaluations limit to be defined:

nf = 1000
Call e05jff ('Function Evaluations Limit', nf, comm, lcomm, ifail)

A complete list of optional parameters, their symbolic names and default values is given in Section 12 in e05jbf.

4 References

None.

5 Arguments

1: $optstr$ – Character(*) Input: On entry: a string identifying an integer-valued optional parameter (as described in Section 12 in e05jbf).
2: $ivalue$ – Integer Input: On entry: an integer value associated with the optional parameter in optstr.
3: $comm (lcomm)$ – Real (Kind=nag_wp) array Communication Array: On exit: comm must not be altered between calls to any of the routines e05jbf, e05jcf, e05jdf, e05jef, e05jff, e05jgf, e05jhf, e05jjf, e05jkf and e05jlf.
4: $lcomm$ – Integer Input: On entry: the dimension of the array comm as declared in the (sub)program from which e05jff is called.

Constraint: $lcomm \geq 100$ .
5: $ifail$ – Integer Input/Output: On entry: ifail must be set to $0$ , $−1$ or $1$ to set behaviour on detection of an error; these values have no effect when no error is detected.
A value of $0$ causes the printing of an error message and program execution will be halted; otherwise program execution continues. A value of $−1$ means that an error message is printed while a value of $1$ means that it is not.

If halting is not appropriate, the value $−1$ or $1$ is recommended. If message printing is undesirable, then the value $1$ is recommended. Otherwise, the value $0$ is recommended. When the value $- 1$ or $1$ is used it is essential to test the value of ifail on exit.

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

6 Error Indicators and Warnings

If on entry

ifail = 0

−1

, explanatory error messages are output on the current error message unit (as defined by x04aaf).

Errors or warnings detected by the routine:

$ifail = 1$: Initialization routine e05jaf has not been called.

On entry, $lcomm = ⟨ value ⟩$ .
Constraint: $lcomm \geq 100$ .

$ifail = 2$: The supplied optional parameter is invalid. A keyword or keyword combination was not recognized.

$ifail = 3$: Attempt to assign a non-positive value of Function Evaluations Limit ( $nf$ ): $nf = ⟨ value ⟩$ .

Attempt to assign a non-positive value of Local Searches Limit ( $loclim$ ): $loclim = ⟨ value ⟩$ .

Attempt to assign a non-positive value of Static Limit ( $stclim$ ): $stclim = ⟨ value ⟩$ .

$ifail = - 99$: An unexpected error has been triggered by this routine. Please contact NAG.
See Section 7 in the Introduction to the NAG Library FL Interface for further information.

$ifail = - 399$: Your licence key may have expired or may not have been installed correctly.
See Section 8 in the Introduction to the NAG Library FL Interface for further information.

$ifail = - 999$: Dynamic memory allocation failed.
See Section 9 in the Introduction to the NAG Library FL Interface for further information.

7 Accuracy

Not applicable.

8 Parallelism and Performance

e05jff is threaded by NAG for parallel execution in multithreaded implementations of the NAG Library.

Please consult the X06 Chapter Introduction for information on how to control and interrogate the OpenMP environment used within this routine. Please also consult the Users' Note for your implementation for any additional implementation-specific information.