SUBROUTINE SCALE(DATA,IDATA)
        COMMON /PLTCOM/IP1P2(2,2),DMNMX(2,2),PMNMX(2,2),IPAPER(2,2)
        COMMON /PLTCOM/LEGWIN(2,2)
        COMMON /PLTCOM/NTICK(2)
        COMMON /PLTCOM/NPEN,NLINE,ISYM,NCNVER,NSTRT,IPLTOK,LEGPOS
        DIMENSION DATA(2),IDATA(2),RIDATA(2)
C...    CONVERTS DATA COORDS DATA TO PLOTTER COORDS IDATA
C...    IF CONVERSION IS NOT POSSIBLE (I.E. IDATA WOULD B OUTSIDE THE
C...    COMPUTER RANGE FOR INTEGERS), NCNVER (IN COMMON) IS INCREMENTED
C...
C...
C...    SCALE SHOULD INITIALLY BE CALLED WITH NCNVER=0.
C...    THEN, NCNVER WILL INDICATE THE TOTAL NUMBER OF CONVERSION
C...    ERRORS SINCE IT WAS SET TO ZERO.
C
C
C...    SCALE (AFFINE TRANSFORMATION)
        DO 10  K=1,2
        I=K
        RIDATA(I)=RFLOOR((DATA(I)-PMNMX(I,1))*(IP1P2(I,2)-IP1P2(I,1))/
     1     (PMNMX(I,2)-PMNMX(I,1))+IP1P2(I,1))
C...    CHECK FOR REAL -> INTEGER  CONVERSION ERROR
        IF(RIDATA(I) .GE. 32768.  .OR.  RIDATA(I) .LT. -32768.) GOTO 20
10      IDATA(I)=RIDATA(I)
        RETURN
C...    CONVERSION ERROR
20      NCNVER=NCNVER+1
        RETURN
        END

        SUBROUTINE UNSCL(DATA,IDATA)
        COMMON /PLTCOM/IP1P2(2,2),DMNMX(2,2),PMNMX(2,2),IPAPER(2,2)
        COMMON /PLTCOM/LEGWIN(2,2)
        COMMON /PLTCOM/NTICK(2)
        COMMON /PLTCOM/NPEN,NLINE,ISYM,NCNVER,NSTRT,IPLTOK,LEGPOS
       DIMENSION DATA(2),IDATA(2)
C
C...    INVERSE OF "SCALE"
C
        DO 10  I=1,2
10      DATA(I)=(IDATA(I)-IP1P2(I,1))*(PMNMX(I,2)-PMNMX(I,1))/
     1     (IP1P2(I,2)-IP1P2(I,1))+PMNMX(I,1)
        RETURN
        END

        FUNCTION ICEIL(X)
C...    ROUNDS X UP TO NTEGER VALUE (REAL -> INTEGER)
        ICEIL=RCEIL(X)
        RETURN
        END

        FUNCTION IFLOOR(X)
C...    ROUNDS X DOWN TO INTEGER VALUE (REAL -> INTEGER)
        IFLOOR=RFLOOR(X)
        RETURN
        END

        FUNCTION RCEIL(X)
C...    ROUNDS X UP TO INTEGER VALUE (REAL -> REAL)
        RCEIL=-RFLOOR(-X)
        RETURN
        END
        FUNCTION RFLOOR(X)
C...    ROUNDS X EOWN TO INTEGER VALUE (REAL -> REAL)
        RFLOOR=AINT(X)
        IF (X .LT. 0.  .AND.  RFLOOR .NE. X) RFLOOR=RFLOOR-1.
        RETURN
        END