## 14.3 Examples

                PROGRAM EX14_3
                PARAMETER (N=50)
                DIMENSION ZMAT(N,N),ZLEV(12),XRAY(N),YRAY(N)

                STEP=1.6/(N-1)
                DO I=1,N
                X=0.0+(I-1)*STEP
                XRAY(I)=X
                DO J=1,N
                  Y=0.0+(J-1)*STEP
                  YRAY(J)=Y
                  ZMAT(I,J)=(X**2.-1.)**2. + (Y**2.-1.)**2.
                END DO
                END DO

                CALL SETPAG('DA4P')
                CALL DISINI
                CALL PAGERA
                CALL COMPLX

                CALL MIXALF
                CALL TITLIN('Shaded Contour Plot',1)
                CALL TITLIN('F(X,Y) = (X[2$ - 1)[2$ + (Y[2$ - 1)[2$',3)
                CALL NAME('X-axis','X')
                CALL NAME('Y-axis','Y')

                CALL SHDMOD('POLY','CONTUR')
                CALL AXSPOS(450,2670)
                CALL GRAF(0.0,1.6,0.0,0.2,0.0,1.6,0.0,0.2)

                DO I=1,12
                  ZLEV(13-I)=0.1+(I-1)*0.1
                END DO

                CALL CONSHD(XRAY,N,YRAY,N,ZMAT,ZLEV,12)

                CALL HEIGHT(50)
                CALL TITLE
                CALL DISFIN
                END

Figure 14.3: Shaded Contour Plot