## 14.3 Examples

                PROGRAM EX14_1
                PARAMETER (N=100)
                DIMENSION X(N),Y(N),Z(N,N)

                FPI=3.14159/180.
                STEP=360./(N-1)
                DO I=1,N
                  X(I)=(I-1.)*STEP
                  Y(I)=(I-1.)*STEP
                END DO

                DO I=1,N
                  DO J=1,N
                    Z(I,J)=2*SIN(X(I)*FPI)*SIN(Y(J)*FPI)
                  END DO
                END DO

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

                CALL TITLIN('Contour Plot',1)
                CALL TITLIN('F(X,Y) = 2 * SIN(X) * SIN(Y)',3)
                CALL NAME('X-axis','X')
                CALL NAME('Y-axis','Y')

                CALL INTAX
                CALL AXSPOS(450,2670)
                CALL GRAF(0.,360.,0.,90.,0.,360.,0.,90.)

                CALL HEIGHT(30)
                DO I=1,9
                  ZLEV=-2.+(I-1)*0.5
                  IF(I.EQ.5) THEN
                    CALL LABELS('NONE','CONTUR')
                  ELSE
                     CALL LABELS('FLOAT','CONTUR')
                  END IF
                 CALL CONTUR(X,N,Y,N,Z,ZLEV)
                END DO

                CALL HEIGHT(50)
                CALL TITLE
                CALL DISFIN
                END

Figure 14.1: Contour Plot