To supply optional parameters to
h02cef from an external file.
h02cff may be used to supply values for optional parameters to
h02cef.
h02cff 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 of up to
characters, consisting of one or more items. The items associated with a given option must be separated by spaces, or equal 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 real value. Such numbers may be up to contiguous characters in Fortran 77's I, F, E or D 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 = 1
End
Normally each line of the file is printed as it is read, on the current advisory message unit (see
x04abf), but printing may be suppressed using the keyword
Nolist. To suppress printing of
Begin,
Nolist must be the first option supplied as in the file:
Begin
Nolist
Print Level = 1
End
Printing will automatically be turned on again after a call to
h02cef and may be turned on again at any time using the keyword
List.
Optional parameter settings are preserved following a call to
h02cef, and so the keyword
Defaults is provided to allow you to reset all the optional parameters to their default values prior to a subsequent call to
h02cef.
A complete list of optional parameters, their abbreviations, synonyms and default values is given in
Section 12 in
h02cef.
None.
If a line is not recognized as a valid option, then a warning message is output on the current advisory message unit (see
x04abf).
Not applicable.
h02cff is not thread safe and should not be called from a multithreaded user program. Please see
Section 3.12.1 in How to Use the NAG Library and its Documentation for more information on thread safety.
h02cgf may also be used to supply optional parameters to
h02cef. Note that if
e04nkf/e04nka is used in the same program as
h02cef, then in general
h02cff will also affect the options used by
e04nkf/e04nka.
This example solves the same problem as the example for
h02cef, but in addition illustrates the use of
h02cff and
h02cgf to set optional parameters for
h02cef.
In this example the options file read by
h02cff is appended to the data file for the program (see
Section 10.2). It would usually be more convenient in practice to keep the data file and the options file separate.