PROGRAM EXA12_1
DIMENSION IXP(4),IYP(4)
DATA IXP/150,1949,1949,150/ IYP/2600,2600,801,801/
EXTERNAL ZFUN
CALL SETPAG('DA4P')
CALL DISINI
CALL PAGERA
CALL COMPLX
CALL AXSPOS(200,2600)
CALL AXSLEN(1800,1800)
CALL NAME('X-axis','X')
CALL NAME('Y-axis','Y')
CALL NAME('Z-axis','Z')
CALL TITLIN('Surface Plot (SURFUN)',2)
CALL TITLIN('F(X,Y) = 2*SIN(X)*SIN(Y)',4)
CALL GRAF3D(0.,360.,0.,90.,0.,360.,0.,90.,-3.,3.,-3.,1.)
CALL HEIGHT(50)
CALL TITLE
CALL SHLSUR
CALL SURFUN(ZFUN,1,10.,1,10.)
C Grid in the XY plane
CALL GRFINI(-1.,-1.,-1.,1.,-1.,-1.,1.,1.,-1.)
CALL NOGRAF
CALL GRAF(0.,360.,0.,90.,0.,360.,0.,90.)
CALL DASHL
CALL GRID(1,1)
CALL GRFFIN
C Grid in the YZ plane
CALL GRFINI(-1.,-1.,-1.,-1.,1.,-1.,-1.,1.,1.)
CALL GRAF(0.,360.,0.,90.,-3.,3.,-3.,1.)
CALL GRID(1,1)
CALL GRFFIN
C Shading in the XZ plane
CALL GRFINI(-1.,1.,-1.,1.,1.,-1.,1.,1.,1.)
CALL SHDPAT(7)
CALL SOLID
CALL AREAF(IXP,IYP,4)
CALL GRFFIN
CALL DISFIN
END
FUNCTION ZFUN(X,Y)
FPI=3.14159/180.
ZFUN=2*SIN(X*FPI)*SIN(Y*FPI)
END
Figure 12.1: Surface Plot