14.3 Examples

            PROGRAM EX14_2
            PARAMETER (N=100)
            DIMENSION ZMAT(N,N)

            STEP=1.2/(N-1)
            DO I=1,N
              X=0.4+(I-1)*STEP
              DO J=1,N
                Y=0.4+(J-1)*STEP
                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('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 AXSPOS(450,2670)
            CALL GRAF(0.4,1.6,0.4,0.2,0.4,1.6,0.4,0.2)

            DO I=1,12
              ZLEV=0.1+(I-1)*0.1
              IF(MOD(I,3).EQ.1) THEN
                CALL SOLID
                CALL THKCRV(3)
              ELSE IF(MOD(I,3).EQ.2) THEN
                CALL DASH
                CALL THKCRV(1)
              ELSE
                CALL DOT
                CALL THKCRV(1)
              END IF

              CALL CONMAT(ZMAT,N,N,ZLEV)
            END DO

            CALL HEIGHT(50)
            CALL TITLE
            CALL DISFIN
            END  

Figure 14.2: Contour Plot