PARAMETER LUNIN = 5		! Normal input LUN.
	PARAMETER LUNOUT = 6		! Normal output LUN.
	PARAMETER MXVARS = 103		! Max. number of variables.
	PARAMETER MXVNAM = 1		! Max var. name len (6-char units)
	PARAMETER MXOPSK = 100		! Max. depth of operation stack.
	PARAMETER MXPSSK = 200		! Max. depth of parser stack.
	PARAMETER MXVLSK = 50		! Max. depth of value stack.
C					! WARNING - IF YOU DON'T KEEP
C					!    MXVLSK*2<MXPSSK YOU'LL BE
C					!    SORRY.
	PARAMETER OPPUSH = -1		! Operator - Push data to stack.
	PARAMETER OPPOP  = -2		! Operator - Pop data off stack.
	PARAMETER OPADD  = -3		! Operator - Add stacked data.
	PARAMETER OPSUB  = -4		! Operator - Subtract stacked.
	PARAMETER OPOR   = -5		! Operator - Logical "or" stack.
	PARAMETER OPMUL  = -6		! Operator - Multiply stacked.
	PARAMETER OPDIV  = -7		! Operator - Divide stacked.
	PARAMETER OPAND  = -8		! Operator - Logical "and" stak.
	PARAMETER OPEXP  = -9		! Operator - Exponentiate stack.
	PARAMETER OPNOT  = -10		! Operator - Logical "not" stak.
	PARAMETER OPNEG  = -11		! Operator - Negate staked data.
	PARAMETER OPCMP  = -12		! Operator - Compare top 2.
	PARAMETER OPSTO  = -13		! Operator - Store top (no pop).
	PARAMETER OPPSHI = -14		! Operator - Push immediate.
	PARAMETER OPSGN  = -15		! Operator - "Signum".
	PARAMETER OPIDIV = -16		! Operator - Integer division.
	PARAMETER OPMOD  = -17		! Operator - Remainder.
	PARAMETER OPABS  = -18		! Operator - Absolute value.
	PARAMETER OPTRUE = -19		! Operator - Load "True".
	PARAMETER OPFALS = -20		! Operator - Load "False".

	INTEGER*4 VARNAM(MXVNAM,MXVARS)	! Variable names.
	REAL*4    VARVAL(MXVARS)	! Variable values.
	INTEGER*2 NVARS			! Number of variables in use.
	INTEGER*2 NVAROL		! "Old" vars in use.
	INTEGER*2 OPPNTR		! Operation stack pointer.
	INTEGER*2 OPSTAK(MXOPSK)	! Operation stack.
	INTEGER*2 PSPNTR		! Parser stack pointer.
	INTEGER*2 PSSTAK(MXPSSK)	! Parser stack.
	INTEGER*2 PTRACE		! LUN to trace parse.
	REAL*4    VALSTK(MXVLSK)	! Intermediate value stack.
	INTEGER*2 VALPTR		! Pointer in value stack.
	INTEGER*2 IRLIDX		! Location of real var.
	INTEGER*2 CURRDX		! Current radix.
	LOGICAL*1 IRXMRK		! Current exponent marker.
	INTEGER*2 SRCLUN		! Source file LUN.
	INTEGER*2 PRESUL		! Index of result.
	INTEGER*2 PRADIX		! Index of current radix.
	INTEGER*2 PTRIM			! Index of trim mask.

	EQUIVALENCE (VALPTR,PSPNTR)	! Since parser and calc. don't
	EQUIVALENCE (VALSTK,PSSTAK)	!   need at same time.

	COMMON /CALCU/ NVARS, NVAROL, NCONS, VARNAM, VARVAL,
     *			OPPNTR, OPSTAK, SRCLUN,
     *			PRESUL, PRADIX, PTRIM,
     *			IRLIDX, CURRDX, PTRACE, PSPNTR, PSSTAK,
     *			IRXMRK