nag_opt_nlp2_option_string (e04wf) may be used to supply individual optional parameters to nag_opt_nlp2_solve (e04wd). The initialization function nag_opt_nlp2_init (e04wc) must have been called before calling nag_opt_nlp2_option_string (e04wf).

Syntax

[iw, rw, ifail] = e04wf(string, iw, rw)

[iw, rw, ifail] = nag_opt_nlp2_option_string(string, iw, rw)

Description

nag_opt_nlp2_option_string (e04wf) may be used to supply values for optional parameters to nag_opt_nlp2_solve (e04wd). It is only necessary to call nag_opt_nlp2_option_string (e04wf) for those arguments whose values are to be different from their default values. One call to nag_opt_nlp2_option_string (e04wf) sets one argument value.

Each optional parameter is defined by a single character string, of up to

72

characters, consisting of one or more items. The items associated with a given option must be separated by spaces, or equals signs

[=]

. Alphabetic characters may be upper or lower case. The string

Print Level = 1

is an example of a string used to set an optional parameter. For each option the string contains one or more of the following items:

–	a mandatory keyword;
–	a phrase that qualifies the keyword;
–	a number that specifies an integer or double value. Such numbers may be up to $16$ contiguous characters in Fortran's I, F, E or D formats, terminated by a space if this is not the last item on the line.

For nag_opt_nlp2_option_string (e04wf), each user-specified option is not normally printed as it is defined, but this printing may be turned on using the keyword List. Thus the statement

[iw, rw, ifail] = e04wf('List', iw, rw);

turns on printing of this and subsequent options. Printing may be turned off again using the keyword Nolist.

Optional parameter settings are preserved following a call to nag_opt_nlp2_solve (e04wd) and so the keyword Defaults is provided to allow you to reset all the optional parameters to their default values before a subsequent call to nag_opt_nlp2_solve (e04wd).

A complete list of optional parameters, their abbreviations, synonyms and default values is given in Optional Parameters in nag_opt_nlp2_solve (e04wd).

References

None.

Parameters

Compulsory Input Parameters

1: $string$ – string: A single valid option string (see Description in nag_opt_nlp2_option_string (e04wf) and Optional Parameters in nag_opt_nlp2_solve (e04wd)).
2: $iw (:)$ – int64int32nag_int array: The dimension of the array iw must be at least $leniw$ (see nag_opt_nlp2_init (e04wc))
3: $rw (:)$ – double array: The dimension of the array rw must be at least $lenrw$ (see nag_opt_nlp2_init (e04wc))

Optional Input Parameters

None.

Output Parameters

1: $iw (:)$ – int64int32nag_int array: The dimension of the array iw will be $leniw$ (see nag_opt_nlp2_init (e04wc))
2: $rw (:)$ – double array: The dimension of the array rw will be $lenrw$ (see nag_opt_nlp2_init (e04wc))
3: $ifail$ – int64int32nag_int scalar: $ifail = 0$ unless the function detects an error (see Error Indicators and Warnings).

Error Indicators and Warnings

Errors or warnings detected by the function:

$ifail = 1$: The initialization function nag_opt_nlp2_init (e04wc) has not been called.

$ifail = 2$: The supplied option is invalid. Check that the keywords are neither ambiguous nor misspelt.

$ifail = - 99$: An unexpected error has been triggered by this routine. Please contact NAG.

$ifail = - 399$: Your licence key may have expired or may not have been installed correctly.

$ifail = - 999$: Dynamic memory allocation failed.

Accuracy

Not applicable.

Further Comments

nag_opt_nlp2_option_integer_set (e04wg) or nag_opt_nlp2_option_double_set (e04wh) may also be used to supply optional parameters to nag_opt_nlp2_solve (e04wd).

Example

Open in the MATLAB editor: e04wf_example

function e04wf_example


fprintf('e04wf example results\n\n');

string = 'Major iterations limit';
itmax = 50;
stropt = sprintf('%s = %4d', string, itmax);

% Initialize
[iw, rw, ifail] = e04wc;
% Set option
[iw, rw, ifail] = e04wf( ...
                         stropt, iw, rw);
% Get option value
[ivalue, iw, rw, ifail] = e04wk( ...
                                 string, iw, rw);

fprintf('%s has been set to %5d\n', string, ivalue);

e04wf example results

Major iterations limit has been set to    50

PDF version (NAG web site, 64-bit version, 64-bit version)

Chapter Contents

Chapter Introduction

NAG Toolbox