NAG Library Function Document

nag_opt_nlp_revcomm_option_set_file (e04udc)


    1  Purpose
    7  Accuracy


To supply optional parameters to nag_opt_nlp_revcomm (e04ufc) from an external file.


#include <nag.h>
#include <nage04.h>
void  nag_opt_nlp_revcomm_option_set_file (Nag_FileID fileid, Nag_Boolean lwsav[], Integer iwsav[], double rwsav[], NagError *fail)


nag_opt_nlp_revcomm_option_set_file (e04udc) may be used to supply values for optional parameters to nag_opt_nlp_revcomm (e04ufc). nag_opt_nlp_revcomm_option_set_file (e04udc) reads an external file and each line of the file defines a single optional parameter. It is only necessary to supply values for those arguments whose values are to be different from their default values.
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.
Blank strings and comments are ignored. A comment begins with an asterisk (*) and all subsequent characters in the string are regarded as part of the comment.
The file containing the options must start with Begin and must finish with End. An example of a valid options file is:
Begin * Example options file 
   Print level = 5 
Optional parameter settings are preserved following a call to nag_opt_nlp_revcomm (e04ufc) 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_revcomm (e04ufc).
A complete list of optional parameters, their abbreviations, synonyms and default values is given in Section 12 in nag_opt_nlp_revcomm (e04ufc).




1:     fileid Nag_FileIDInput
On entry: the ID of the option file to be read as returned by a call to nag_open_file (x04acc).
2:     lwsav[120] Nag_BooleanCommunication Array
3:     iwsav[610] IntegerCommunication Array
4:     rwsav[475] doubleCommunication Array
The arrays lwsav, iwsav and rwsav MUST NOT be altered between calls to any of the functions nag_opt_nlp_revcomm_option_set_file (e04udc), nag_opt_nlp_revcomm_option_set_string (e04uec), nag_opt_nlp_revcomm (e04ufc) or nag_opt_nlp_revcomm_init (e04wbc).
5:     fail NagError *Input/Output
The NAG error argument (see Section 3.7 in How to Use the NAG Library and its Documentation).

Error Indicators and Warnings

Dynamic memory allocation failed.
See Section in How to Use the NAG Library and its Documentation for further information.
On entry, argument value had an illegal value.
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.
One or more lines of the options file is invalid.
End-of-file was found before Begin was found.
Begin was found, but end-of-file was found before End was found.
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.
Could not open options file with fileid=value.


Not applicable.

Parallelism and Performance

nag_opt_nlp_revcomm_option_set_file (e04udc) is not threaded in any implementation.

Further Comments

nag_opt_nlp_revcomm_option_set_string (e04uec) may also be used to supply optional parameters to nag_opt_nlp_revcomm (e04ufc).


This example solves the same problem as the example for nag_opt_nlp_revcomm (e04ufc), but in addition illustrates the use of nag_opt_nlp_revcomm_option_set_file (e04udc) and nag_opt_nlp_revcomm_option_set_string (e04uec) to set optional parameters for nag_opt_nlp_revcomm (e04ufc).

Program Text

Program Text (e04udce.c)

Program Data

Program Options (e04udce.opt)

Program Data (e04udce.d)

Program Results

Program Results (e04udce.r)

© The Numerical Algorithms Group Ltd, Oxford, UK. 2017