C     [DEM38]
C     DEMONSTRATION PROGRAM FOR PLTRI. THE PRINCIPAL POINT OF INTEREST
C     IN THIS DEMONSTRATION IS THE FACT THAT VIRTUALLY ANY COORDINATE
C     SYSTEM MAY BE USED FOR PLOTTING A GRAPH, AND THAT THE AXIS DRAWING
C     OPTION WILL FAITHFULLY DRAW THE COORDINATE AXES OF THE SYSTEM IN
C     USE. BY SELECTING OPTIONS L=1,2,3,4,5, THE FIVE COORDINATE SYSTEMS
C     CARTESIAN, POLAR, ELLIPTIC, SPHERICAL POLAR, OR TRIANGULAR, MAY BE
C     TESTED.
C     [07-JUN-75]

      EXTERNAL    PLTCA,PLTPO,PLTEL,PLTSP,PLTTR

      EX(TE)=0.5*(1.0+SIN(0.5*TE*(1.0+0.5*TE)))
      WY(TE)=0.4*(COS(TE)+0.3*COS(2.0*TE)+0.1*COS(3.0*TE))

      DT=0.005
      L=3
      N=1001
      CALL PLT00
      CALL PLTBO
      CALL PLTLA ('DEM38')
      CALL PLTIG (0.0,0.0,1,PLTPO)
      CALL PLTIG (1.0,1.0,2,PLTPO)
      TE=0.0
      IF (L.EQ.1) CALL PLTIG (EX(TE),WY(TE),3,PLTCA)
      IF (L.EQ.2) CALL PLTIG (EX(TE),WY(TE),3,PLTPO)
      IF (L.EQ.3) CALL PLTIG (EX(TE),WY(TE),3,PLTEL)
      IF (L.EQ.4) CALL PLTIG (EX(TE),WY(TE),3,PLTSP)
      IF (L.EQ.5) CALL PLTIG (EX(TE),WY(TE),3,PLTTR)
      DO 10 I=1,N
      IF (L.EQ.1) CALL PLTIG (EX(TE),WY(TE),4,PLTCA)
      IF (L.EQ.2) CALL PLTIG (EX(TE),WY(TE),4,PLTPO)
      IF (L.EQ.3) CALL PLTIG (EX(TE),WY(TE),4,PLTEL)
      IF (L.EQ.4) CALL PLTIG (EX(TE),WY(TE),4,PLTSP)
      IF (L.EQ.5) CALL PLTIG (EX(TE),WY(TE),4,PLTTR)
   10 TE=TE+DT
      TE=0.0
      DO 20 I=1,11
      IF (L.EQ.1) CALL PLTIG (TE,TE,5,PLTCA)
      IF (L.EQ.2) CALL PLTIG (TE,TE,5,PLTPO)
      IF (L.EQ.3) CALL PLTIG (TE,TE,5,PLTEL)
      IF (L.EQ.4) CALL PLTIG (TE,TE,5,PLTSP)
      IF (L.EQ.5) CALL PLTIG (TE,TE,5,PLTTR)
   20 TE=TE+0.1
      TE=0.0
      DO 30 I=1,21
      IF (L.EQ.1) CALL PLTIG (EX(TE),WY(TE),6,PLTCA)
      IF (L.EQ.2) CALL PLTIG (EX(TE),WY(TE),6,PLTPO)
      IF (L.EQ.3) CALL PLTIG (EX(TE),WY(TE),6,PLTEL)
      IF (L.EQ.4) CALL PLTIG (EX(TE),WY(TE),6,PLTSP)
      IF (L.EQ.5) CALL PLTIG (EX(TE),WY(TE),6,PLTTR)
   30 TE=TE+0.05
      CALL PLTEJ
      CALL EXIT
      END

