SUBROUTINE PARSCO (IERR,STRNG,LSTRN,NPNTS,PARM,PARMO)
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C
C	TITLE:  PARSCO.FTN - COORDINATE INPUT PARSER
C
C	AUTHOR:	T V ATKINSON
C		DEPARTMENT OF CHEMISTRY
C		MICHIGAN STATE UNIVERSITY
C		EAST LANSING, MI 48824
C
C	DATE:  27-JUN-82
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C
C	  THIS ROUTINE PARSES A STRING OF CHARACTERS AND RETURNS THE
C	X,Y COORDINATES IN PHYSICAL UNITS FOR ONE OR MORE POINTS.  THE
C	STRING HAS THE GENERAL FORM AS FOLLOWS
C
C		RRR...RRR/S1/S2,RRR ... RRR/S3/S4, .....
C
C	WHERE RRR ... RRR IS ANY VALID FORTRAN FLOATING POINT NUMBER,
C	/SI ARE ANY OF THE SWITCHES LISTED BELOW.  THE FIRST NUMBER
C	DECODED IN THE STRING WILL BE THE X-COORDINATE OF THE FIRST
C	POINT.  THE SECOND NUMBER DECODED WILL BE THE Y-COORDINATE OF
C	THE FIRST POINT,  THE THIRD NUMBER DECODED WILL BE THE X-COOR-
C	DINATE OF THE SECOND POINT. ETC.  THE SWITCHES CAUSE THE NUMBERS
C	AS DECODED TO BE TRANSFORMED AS DESCRIBED BELOW.  FOR FURTHER
C	DISCUSSION SEE THE MULPLT DOCUMENTATION.
C	  WHEN POLAR COORDINATE INPUT IS SELECTED, THERE MUST BE ONE ANGLE
C	ENTRY AND ONE RADIUS ENTRY.  THEY MUST ALSO NOT CROSS POINT
C	BOUNDRIES.
C	  THE MODE OF GROUPS 1 AND 2 REMAINS THE SAME UNTIL CHANGED.

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C
C	SWITCHES
C
C		(GROUP 1A)
C
C		/AB	COORDINATE IS ABSOLUTE
C		/RE	COORDINATE IS RELATIVE TO CURRENT LOCAL ORIGIN
C		/IN	COORDINATE IS AN INCREMENT TO BE ADDED TO THE 
C			  VALUE OF THE CORRESPONDING COORDINATE FOR THE
C
C		(GROUP 1B)
C
C		/PA	POLAR COORDINATES - ANGLE
C		/PR	POLAR COORDINATES - RADIUS
C			  LAST POINT PROCESSED.
C
C		(GROUP 2)
C
C		/PH	COORDINATE IS IN PHYSICAL UNITS
C		/PL	COORDINATE IS IN THE PLOT SPACE (I.E., THATTHE UNITS
C			  ARE THOSE OF THE AXIS FOR THAT TYPE PARAMETER
C			  (X OR Y)
C		/RW	COORDINATE IS IN THE UNSCALED, UNOFFSET SPACE
C
C		(GROUP 3)
C
C		/OR	COORDINATE BECOMES THE NEW ORIGIN FOR THAT 
C
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C	ARGUMENT LIST:
C
C		STRNG	BYTE ARRAY CONTAINING STRING TO BE PARSED
C
C		LSTRN	NUMBER OF BYTES IN STRNG
C
C		NPNTS	NUMBER OF POINTS TO BE DECODED
C
C		PARM	ARRAY CONTAINING LAST VALUES OF THE PARAMETERS
C			AND TO RECEIVE THE NEW PARAMETERS.  THE DIMENSION
C			OF PARM IS 2*NPNTS
C
C		PARMO	ARRAY OF DIMENSION 4 WHICH CONTAINS THE LOCAL
C			ORIGIN USED IN RELATIVE MODE AND THE COORDINATES
C			OF THE LAST POINT PROCESSED.
C
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