100 C	P?S/8 FOCAL DISPLAY DEMO PROGRAM
 110 C	DISPLAYS SINE(X)/X   [PRACTICAL INPUTS BETWEEN -20 AND +20]
 120 C	LAST EDIT:	03-DEC-1985	11:00:00	CJL
 130 1.10	ERASE
 140 C	VALUES FOR VT-8/E VERSION:
 150 1.20	S MX=-94;S GX=94;S MY=-100;S GY=99;S HOM=29;S EOS=31
 160 C	VALUES FOR VC12, AX08 VERSION:
 170 C 1.20	S MX=-256;S GX=255;S MY=-256;S GY=255
 180 C	SET X AND Y RANGES FROM VERSION-DEPENDENT PARAMETERS
 190 1.25	S XR=GX-MX;S YR=GY-MY
 200 C	INITIALIZE SCREEN AND SCALE LIMITS; GIVE INITIAL BLURB
 210 1.30	S D=FDIS();S MA=-1E40;S MI=-MA;T "P?S/8 FOCAL DISPLAY SINE(X)/X DEMO
 220 1.30	S D=FDIS();S MA=-1E40;S MI=-MA
 230 1.35	T "P?S/8 FOCAL DISPLAY SINE(X)/X DEMONSTRATION PROGRAM"
 240 1.37	T !,"ENTER LIMITS"
 250 C	GET LOWER AND UPPER LIMITS FOR DISPLAY
 260 1.40	A !,?LOWER? ?UPPER? "# OF " ?POINTS?
 270 C	CALCULATE ALL POINTS ONCE TO ESTABLISH DISPLAY BOUNDS
 280 1.50	S IN=(UP-LO)/PO;F X=LO,IN,UP;D 2
 290 C	HAVING FOUND ALL POINTS, NOW DISPLAY THEIR SCALED REPRESENTATIONS
 300 1.60	S YS=MA-MI;S J=-1;F X=LO,IN,UP;D 4
 310 C	FINAL DISPLAY LINES FOR VT-8/E VERSION:
 320 1.70	O F;S D=FIO(HOM)+FIO(EOS)
 330 1.75	T !!!!!,"PLOT OF SINE(X)/X";S D=FIO(-1);O O
 340 C	FINAL DISPLAY LINE FOR VC12, AX08 VERSION:
 350 C 1.70	T !!,"PLOT OF SINE(X)/X"
 360 1.80	QUIT
 370 C	ROUTINE TO FIND THE EXTREME VALUES
 380 2.10	D 3;I (MA-RE)2.6,2.3
 390 2.20	I (RE-MI)2.4
 400 2.30	R
 410 2.40	S MI=RE
 420 2.50	R
 430 2.60	S MA=RE
 440 C	FUNCTION CALCULATION ROUTINE
 450 3.10	S RE=FSIN(X)/X
 460 C	DISPLAY ROUTINE
 470 4.10	S J=J+1;D 3
 480 4.20	S D=FDIS(((J/PO)*XR)+MX,(((RE-MI)/YS)*YR)+MY)
 490 C	"GROWING DISPLAY" LINE FOR VC12, AX08 VERSION
 500 C 4.30	S D=FDIS(1)