NAG C Library Function Document

nag_opt_nlp_option_set_string (e04wfc) may be used to supply individual optional parameters to nag_opt_nlp_solve (e04wdc). The initialization function nag_opt_nlp_init (e04wcc) must have been called before calling nag_opt_nlp_option_set_string (e04wfc).

2

Specification

#include <nag.h>

#include <nage04.h>

void	nag_opt_nlp_option_set_string (const char string, Nag_E04State state, NagError *fail)

3

Description

nag_opt_nlp_option_set_string (e04wfc) may be used to supply values for optional parameters to nag_opt_nlp_solve (e04wdc). It is only necessary to call nag_opt_nlp_option_set_string (e04wfc) for those arguments whose values are to be different from their default values. One call to nag_opt_nlp_option_set_string (e04wfc) sets one argument value.

Each optional parameter is defined by a single character string, 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 $40$ contiguous characters which can be read using C's d or g formats, terminated by a space if this is not the last item on the line.

For nag_opt_nlp_option_set_string (e04wfc), 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

e04wfc ("List", &state, &fail);

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_nlp_solve (e04wdc) 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_nlp_solve (e04wdc).

A complete list of optional parameters, their abbreviations, synonyms and default values is given in Section 12 in nag_opt_nlp_solve (e04wdc).

4

References

None.

5

Arguments

1: $string$ – const char *Input: On entry: a single valid option string (see Section 3 in nag_opt_nlp_option_set_string (e04wfc) and Section 12 in nag_opt_nlp_solve (e04wdc)).
2: $state$ – Nag_E04State *Communication Structure: state contains internal information required for functions in this suite. It must not be modified in any way.
3: $fail$ – NagError *Input/Output: The NAG error argument (see Section 3.7 in How to Use the NAG Library and its Documentation).

6

Error Indicators and Warnings

NE_ALLOC_FAIL: Dynamic memory allocation failed.
See Section 2.3.1.2 in How to Use the NAG Library and its Documentation for further information.
NE_BAD_PARAM: On entry, argument $〈value〉$ had an illegal value.
NE_E04_OPTION_INVALID: The supplied option is invalid. Check that the keywords are neither ambiguous nor misspelt. The option string is ‘ $〈value〉$ ’.
NE_E04WCC_NOT_INIT: The initialization function nag_opt_nlp_init (e04wcc) has not been called.
NE_INTERNAL_ERROR: An internal error has occurred in this function. Check the function call and any array sizes. If the call is correct then please contact NAG for assistance.
See Section 2.7.6 in How to Use the NAG Library and its Documentation for further information.
NE_NO_LICENCE: Your licence key may have expired or may not have been installed correctly.
See Section 2.7.5 in How to Use the NAG Library and its Documentation for further information.