EXTERNAL ESUB
      REAL*4 X(8),Y(8),E(8)
      CALL VATT
      DO 100 I=1,8
      X(I)=I
      Y(I)=2.0**I
100   E(I)=X(I)*3.0
      DO 200 I=1,2
      CALL PAGE
      CALL XAXIS(1.0,8.0,1.0,1.0)
      CALL YAXIS(0.0,300.0,100.0,1.0,7.0)
      CALL PLTARR(8,4,4,X,Y,1,1,0.0)
      IF(I.EQ.1)CALL ERRBAR(E)
      IF(I.EQ.2)CALL ERRCAL(ESUB)
      CALL ENDPLT
200   CONTINUE
      CALL VDET
      STOP
      END
      SUBROUTINE ESUB(X,Y,E,DUMMY)
      E=X*3.0
      RETURN
      END