230 Y = 0: REM ********************************************************************************************************************************************************************************************************
240 Z = 0: REM ********************************************************************************************************************************************************************************************************
250 RETURN
260 TEXT : HOME
270 PRINT "THE EQUATIONS ARE:"
280 VTAB 3: LIST 230: VTAB 4: HTAB 1: PRINT " ": VTAB 20: HTAB 1: PRINT "<SPACE> TO SEE 'Z' EQUATION": PRINT "<P> TO PLOT EQUATIONS": PRINT "<ESC> FOR MAIN MENU ";: GOSUB 150
290 IF A$ = CHR$(27) THEN 1710
300 IF A$ = "P" THEN 360
310 VTAB 2: CALL -958
320 VTAB 3: LIST 240: CALL -958: VTAB 4: HTAB 1: PRINT " ": VTAB 20: HTAB 1: PRINT "<SPACE> TO SEE 'Y' EQUATION"
330 PRINT "<P> TO PLOT THE EQUATIONS": PRINT "<ESC> FOR MAIN MENU ";: GOSUB 150: IF A$ = " " THEN 260
1930 INVERSE : PRINT ">>CATALOG OVER<<";: GET A$: NORMAL : PRINT
1940 IF Q% = 8 THEN VTAB 20: HTAB 1: PRINT "QUIT THE PROGRAM (Y/N) ? ";: GOSUB 150: PRINT A$;: IF A$ = "Y" THEN END
1950 IF Q% = 6 THEN 2320
1960 IF Q% < >1 OR T% = 0 THEN 1710
1970 REM SAVE GRAPH ROUTINE
1980 TEXT : HOME
1990 INVERSE : HTAB 13: PRINT "SAVE THE GRAPH": HTAB 13: PRINT "--------------": NORMAL : REM 15 -'S
2000 VTAB 5: PRINT "ENTER THE GRAPH NAME:": INPUT "";N$:NF = 1: IF LEN(N$) = 0 THEN 1710
2010 FOR NC = 1 TO LEN(N$):NA = ASC( MID$ (N$,NC,1))
2020 NF = ((NA >64 AND NA <91) OR (NA = 46) OR (NA >47 AND NA <58 AND NC >1)) AND NF = 1: NEXT : IF LEN(N$) >11 OR NF = 0 OR LEFT$(N$,1) = "." THEN PRINT "INVALID NAME": GOTO 2000
2030 PRINT : PRINT "INSERT DISK INTO SLOT ";S$;" ,DRIVE ";D1$: PRINT
2040 PRINT "O.K. TO SAVE ? (Y/N) ";: GOSUB 150: IF A$ < >"Y" THEN 1710
2190 TEXT : HOME : HTAB 14: PRINT "LOAD A GRAPH": HTAB 14: PRINT "------------": PRINT : REM 13 -'S
2200 VTAB 5: PRINT "INPUT THE GRAPH NAME, WITHOUT GPH OR TXT"
2210 INPUT "";N$:NF = 1: IF LEN(N$) = 0 THEN 1710
2220 FOR NC = 1 TO LEN(N$):NA = ASC( MID$ (N$,NC,1))
2230 NF = ((NA >64 AND NA <91) OR (NA = 46) OR (NA >47 AND NA <58 AND NC >1)) AND NF = 1: NEXT : IF LEN(N$) >11 OR NF = 0 OR LEFT$(N$,1) = "." THEN PRINT "INVALID NAME": GOTO 2210
2240 PRINT : PRINT "INSERT DISK INTO SLOT ";S$;" DRIVE ";D1$
2250 PRINT : PRINT "O.K. TO LOAD ? (Y/N) ";: GOSUB 150: PRINT : IF A$ < >"Y" THEN 1710
2510 TEXT : HOME : POKE 216,0:Q% = PEEK(222): PRINT : PRINT "ERROR NUMBER ";Q%: PRINT "HAS OCCURED DURING DISK ACCESS": GET A$: GOTO 1710
2520 REM SHAPE TABLE POKER
2530 POKE 232,0: POKE 233,16: RESTORE : FOR I = 1 TO 39: READ Q%: POKE 4095 +I,Q%: NEXT
2540 DATA 2,0,6,0,19,0,24,8
2550 DATA 54,27,43,45,41,45
2560 DATA 26,27,51,6,0,24,8
2570 DATA 56,63,63,54,54,54
2580 DATA 45,45,45,45,45,36
2590 DATA 36,36,63,63,7,0
2600 FOR I = 1 TO 3: READ Q$:T$(I) = Q$: NEXT
2610 DATA "CARTESIAN"
2620 DATA "SEMI-LOG"
2630 DATA "LOG-LOG"
2640 FOR I = 768 TO 873: READ Q%: POKE I,Q%: NEXT : RETURN
2650 DATA 32,190,222,32,227,223,165,184,133,29,165,185,133,30,160,2,177,131,133,28,136,177,131,133,27,136,177,131,72,169,0,160,200,153,0,2,169,42,136,153,0,2,136,208,250,104,168,136,177,27,153
2660 DATA 0,2,192,0,208,246,160,4,132,19,162,255,32,108,213,169,230,133,80,169,0,133,81,32,26,214,165,155,133,25,165,156,133,26,160,5,200,185,250,1,240,4,145,155,208,246,165,29,133,184,165,30,133,185,96