	PROGRAM TEST4
	DIMENSION X(512),Y(512),IBUF(30)
	DO 10 I=1,512
	X(I)=ALOG10(FLOAT(I))
	R=(6.2832)*FLOAT(I)/200.
	Y(I)=SIN(R)
10	CONTINUE
	CALL VTCLR
	CALL BOUNDS(1,X,XMAX,XMIN,512,0,0,0)
	CALL BOUNDS(1,Y,YMAX,YMIN,512,0,0,0)
	CALL GRINIT(IBUF)
	CALL GRREGN(IBUF,0,3)
	CALL GRCLN(IBUF,0)
	CALL GRSCAL(IBUF,XMIN,XMAX,YMIN,YMAX,0)
	CALL GRFRAM(IBUF,0,227)
	call vthtxt(8,23,1,' Point plot graph drawing ')
	DO 50 I=1,512
	I1=513-I
	CALL GRPNTS(IBUF,0,X(I1),Y(I1),0)
50	CONTINUE
	call vtroll(1,24)
	call vtelin(2,23)
	call vthtxt(8,23,1,' Now, add y-axis markers ')
	CALL VTMCUR(20,1)
	DO 100 I=1,10
	XUSR=((FLOAT(I)/10.)*(YMAX-YMIN))+YMIN
	CALL GRHLIN(IBUF,XUSR,0)
100	CONTINUE
	CALL SLEEP(10)
	call vtclr
	CALL EXIT
	END

