THE PPP DISC CONTAINS TWO COPIES OF THE PPP PROGRAM,
PLOT PROGRAM  AND FOUR EXE FILES WITH THE- INPUT FOR
TWO DEMONSTRATION RUNS FOR EACH ONE OF THEM.
THE COPY OF CODE FILES, WITH SUFFIX BAK IS FOR BACKUP
PURPOSES.
FOR EXECUTION OF THE PROGRAMS IT IS NECESSARY TO TOGGLE
THE SWAP ON WITH THE S COMMAND (OTHERWIS THE STACK OVERFLOW
ERROR WILL BE GENERATED AT THE BEGINNING OF DI CALCULATON)
AND TO GIVE COMMAND X (#5:) PPP OR X (#5:)PLOT. THEN EITHER
THE INPUT IS GIVEN FROM KEIBOARD OR AN EXEC FILE WITH THE
LINES OF INPUT IS RUN.
IN THIS CASE CARE SHOULD BE TAKEN OF THE RULES FOR THE
HANDLING THIS KIND OF FILES SEE APPLE PASCAL MANUALS).
THE PROGRAMS ASKS FOR THE OUTPUT DEVICE.
POSSIBLE ANSWERS ARE C FOR CONSOLE, P FOR LINE PRINTER
C FOR COMMUNICATION INTERFACE.
THE INPUT TO THE PPP PROGRAM ISEXACLY THE SAME AS THE
ORIGINAL ICL VERSION OF THE SAME PROGRAM (UNIVERSITY
OF LEEDS).
PROGRAM HAS THE SAME INPUT AS THE PPP PROGRAM. IT COMPUTES
THE MOLECULAR GEOMETRY AND DISPLAYS THE MOLECULE ON THE
CONSOLE, WHEN THE DRAWING IS FINISHED.
THE PROGRAM ASKS WHETHERTHE OUTPUT OF THE INPUT AND THE
GEOMETRICAL PARAMETERS ARE WANTED. IN THIS CASE ANSWER C
OTHERWISE ANSWER A TO MAKE THE PROGRAM STOP.
THE MAXIMUM NUMBER OF ATOMS AND TRANSITION ACCEPTED BY
THE PROGRAM IS 30.

TAKE NOTICE OF THE FACT THAT THE PROGRAM IS SEGMENTED.
THEREFOR THE PPP DISK MUST BE IN THE DISK DRIVE UP TO
THE END OF THE RUN.
TO EXECUTE THE EXAMPLES WITHOUT MODIFICATIONS THE PPP
DISK MUST BE IN THE DRIVE #5.
IF ONE WANT EXECUTION WITH THE PPP DISK IN THE DRIVE #4
IT IS NECESSARY CHANGE THE NUMBER IN THE FIRST LINE OF EACH
EXEC FILE.