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Error messages

  With respect to error messages it has been decided to use the so-called "hard" option, which means that immediately after an error an error message will be given and if necessary the program is halted.
The soft option, which means returning with an error number in the parameter list is only applied if a numerical method produced an error, for example because no convergence appeared.
It is advised to use a standard subroutine that produces the error messages and also delivers a trace back if possible. This subroutine should be such that an error message is clearly visible in the output file by producing sufficient blank lines and a clear indicator. An alternative is to write the error messages to a separate file. However, experience learns that user are not inclined to read this file and as a consequence errors might not be noted. For that reason it is advised to write errors to the standard output file.
There must be a clear distinction between errors and warnings. If too much errors have been produced, stop the program, if there are too much warnings, suppress subsequent warnings.
In SEPRAN all errors must be given by the error subroutine ERRSUB and all warnings by ERRWAR.
In ISNaS the error subroutine is called ISERRSUB and the warning subroutine ISWARSUB. These subroutines have already been adapted for a parallel environment.


ISNaS ontwikkeling
Wed May 24 08:37:14 METDST 1995