PROGRAM EXA12_2
CHARACTER*60 CTIT1,CTIT2
EXTERNAL ZFUN
CTIT1='Surface Plot of the Parametric Function'
CTIT2='[COS(t)*(3+COS(u)),
* SIN(t)*(3+COS(u)), SIN(u)]'
PI=3.14159
CALL SETPAG('DA4P')
CALL METAFL('POST')
CALL DISINI
CALL HWFONT
CALL PAGERA
CALL AXSPOS(200,2400)
CALL AXSLEN(1800,1800)
CALL INTAX
CALL TITLIN(CTIT1,2)
CALL TITLIN(CTIT2,4)
CALL NAME('X-axis','X')
CALL NAME('Y-axis','Y')
CALL NAME('Z-axis','Z')
CALL VKYTIT(-300)
CALL GRAF3D(-4.,4.,-4.,1.,-4.,4.,-4.,1.,
* -3.,3.,-3.,1.)
CALL HEIGHT(40)
CALL TITLE
CALL SURMSH('ON')
STEP=2*PI/30.
CALL SURFCP(ZFUN,0.,2*PI,STEP,0.,2*PI,STEP)
CALL DISFIN
END
FUNCTION ZFUN(X,Y,IOPT)
IF(IOPT.EQ.1) THEN
ZFUN=COS(X)*(3+COS(Y))
ELSE IF(IOPT.EQ.2) THEN
ZFUN=SIN(X)*(3+COS(Y))
ELSE
ZFUN=SIN(Y)
END IF
END
Figure 12.2: Surface Plot of a Parametric Function