Preliminary
Comments - The Input Processor
The DMAREL input dataset consists of a number of steps each containing
one or more directives which together form the main menu of the program.
Each directive consists of a four character keyword. Each of these directives
may have data read in from the same record, or may instruct the program
to read in further records before the next directive. These further records
may consist of data, or they may be sub-directives instructing the program
to choose one of several paths from a separate menu. For example, the
potential input step has one directive, POTE,
which instructs the program to read in potential information from subsequent
records. The potential information is read in using a separate menu and
records containing the data. The potential input menu contains a directive
ENDS which instructs the
program to return to the main menu. Care is needed in ordering the directives
not to put a directive in the wrong place, for example a directive from
the main menu when a sub-directive from the potential input menu is expected.
Any errors detected in the input processor may not necessarily cause the
program to stop immediately to allow inexperienced users to find several
errors in one run. A blank record is ignored if it is encountered when
a directive from the main menu was expected, but not elsewhere. The steps
in a DMAREL job are outlined in table [STEPS TABLE]
in the order in which they should be run, together with the directives
from the main menu used in each step. A number of the directives are redundant
but are kept for compatibility or future developments.
| JOB STEP | DIRECTIVES | COMMENTS |
| TITLE | TITL | Optional |
| SETUP | ||
| CUTOFFS | CUTO, RDMA | Mandatory |
| DEFAULT PARAMETER | IREC, DUMP, PRIN, | Optional |
| CHANGES | ACCU, ACCM, DBAS | |
| CHGC, SCAL, CLUS | ||
| SYMM, FDAT, ZVAL | ||
| UNIT CELL SETUP | LATT | Mandatory. |
| BASI | Order of directives, must not be varied. | |
| POTENTIAL INPUT | POTE | Mandatory |
| ENDS | ||
| MOLECULE INPUT | MOLE | Mandatory |
| ENDS | ||
| UNIT CELL | THBO | For future development |
| THREE-BODY SETUP | ENDS | |
| UNIT CELL | TORS | For future development |
| TORSION SETUP | ENDS | |
| PERFECT LATTICE | STAR PLUT | |
| CALCULATION | ||
| STOP | STOP |
The order of the job steps should not be varied, although variation from this order is permitted in certain cases. Firstly, some of the directives to change default parameters may be more conveniently placed later in the dataset. Where this is so it will be discussed in the section on the individual directives, and the default directives should otherwise always be placed where indicated. Secondly, the title step may appear more than once, anywhere in the sequence given above.
UNIDENTIFIED DIRECTIVE FOUND IN INPUT DATA. THE INPUT LINE IS AS FOLLOWS.
This error does
not cause the program to stop immediately. Further errors will be sought
before the program stops. Check that the directive has been spelt correctly.
Also this error message can arise if the input dataset is in the wrong
order, and the input processor attempts to process either data or a directive
from one of the sub-menus as a directive from the main menu.