The Best of Creative Computing Volume 1 (published 1976)
Escape (BASIC program code)
00050 REM ***ESCAPE VERSION 5, MAY 01ST 1974 ***
00055 REM *****COPYRIGHT CHELSEA COLLEGE ****
00060 LET M=6E+24
00065 LET R=6,37E*6
00070 LET G=6,67E-11
00075 LET R=G*M/R
00080 REM *****MOTION OF OBJECT LAUNCHED VERTICLLY*****
00085 PRINT "WHAT OUTPUT DO YOU WANT?"
00090 PRINT "TYPE 1 FOR LAUNCH VELOCITY TO REACH A CHOSEN HEIGHT"
00095 PRINT " OR 2 FOR VELOCITY AT DIFFERENT HEIGHTS, FOR A CHOSEN"
00100 PRINT " LAUNCH VELOCITY"
00105 PRINT " OR 3 FOR HEIGHT REACHED FOR A CHOSEN LAUNCH VELOCITY"
00110 INPUT A
00115 PRINT
00120 PRINT
00125 PRINT "TO INTERRUPT THE PROGRAM TO GET DIFFERENT OUTPUT"
00130 PRINT "TYPE 0 WHEN YOU ARE ASKED TO INPUT MASS, OR HEIGHT"
00135 PRINT
00140 IF A=1 THEN 165
00145 IF A=2 THEN 280
00150 IF A=3 THEN 500
00155 PRINT "REPLY WITH 1,2 OR 3"
00160 GOTO 110
00165 REM ***GIVES LAUNCH VELOCITY NEEDED FOR A CHOSEN HEIGHT*****
00170 PRINT "MASS OF PROBE (KG) HEIGHT (M) LAUNCH VELOCITY (M/S)"
00175 PRINT
00180 INPUT M1
00185 IF M1=0 THEN 620
00190 IF M1>0 THEN 205
00195 PRINT "POSITIVE MASS ONLY"
00200 GOTO 175
00205 PRINT TAB(24);
00210 INPUT H
00215 IF H=0 THEN 620
00220 IF H>0 THEN 235
00225 PRINT "HEIGHT MUST BE POSITIVE"
00230 GOTO 205
00235 GOSUB 1190
00240 PRINT TAB(40);V
00245 IF H>1000 THEN 255
00250 GOSUB 1160
00255 GOTO 175
00260 REM *GIVES SPEED AT VARIOUS HEIGHT FOR CHOSEN LAUNCH VELOCITY
00265 LET N2=0
00270 PRINT "LAUNCH VELOCITY (M/S)=";
00275 INPUT V1
00280 PRINT
00285 IF V1>0 THEN 300
00290 PRINT "POSITIVE VALUE FOR ";
00295 GOTO 270
00300 PRINT "MASS OF PROBE (KG)=";
00305 INPUT M1
00310 IF M1=0 THEN 620
00315 PRINT
00320 IF M1>0 THEN 335
00325 PRINT "POSITIVE VALUE FOR ";
00330 GOTO 300
00335 LET E1=5*M1*V1*V1
00340 PRINT "TYPE 5 HEIGHTS AT WHICH YOU WOULD LIKE TO KNOW"
00345 PRINT "WHAT VELOCITY THE PROBE HAS LEFT"
00350 PRINT
00355 PRINT " HEIGHT (METRES) VELOCITY (M/S)"
00360 PRINT
00365 FOR I=1 TO 5
00370 INPUT H
00375 IF H=0 THEN 620
00380 IF H>0 THEN 395
00385 PRINT "POSITIVE HEIGHT ONLY"
00390 GOTO 370
00395 LET E=E1=K*M1*H/(R*H)
00400 IF E>0 THEN 415
00405 PRINT TAB(19);"DOESN'T GET THAT FAR"
00410 GOTO 435
00415 GOSUB 1195
00420 PRINT TAB(25);V
00425 IF H>1000 THEN 435
00430 GOSUB 1160
00435 NEXT I
00440 LET N2=N2+1
00445 IF N2=10 THEN 625
00450 PRINT
00455 PRINT "DO YOU WANT TO RUN THIS PART OF THE PROGRAM AGAIN"
00460 PRINT "TYPE 0 FOR NO, OR 1 FOR YES";
00465 INPUT B2
00470 IF B2*(B2-1)<>0 THEN 460
00475 PRINT
00480 PRINT
00485 PRINT
00490 IF B2=0 THEN 270
00500 REM "GIVES MAX HEIGHT REACHED FOR A CHOSEN LAUNCH VELOCITY**
00505 PRINT "MASS OF PROBE (KG) LAUNCH VELOCITY (M/S) ";
00510 PRINT "HEIGHT REACHED (M)"
00515 INPUT M1
00520 IF M1>0 THEN 540
00525 IF M1=0 THEN 620
00530 PRINT "POSITIVE MASS ONLY"
00535 GOTO 515
00540 PRINT TAB(24);
00545 INPUT V1
00550 IF V1>0 THEN 575
00555 IF V1=0 THEN 620
00560 PRINT "POSITIVE VELOCITIES ONLY"
00565 GOTO 540
00570 PRINT
00575 LET E1=.5*M1*V1*V1
00580 IF E1<K*M1 THEN 595
00585 PRINT TAB(50);"WILL NEVER RETURN"
00590 GOTO 510
00595 LET H=(R*E1)/(K*M1-E1)
00600 PRINT TAB(50);M
00605 IF H>=1000 THEN 615
00610 GOSUB 1160
00615 GOTO 515
00620 PRINT
00625 REM **** OFFER INITIAL CHOICE AGAIN, OR TABLE OR GRAPH*****
00630 PRINT
00635 PRINT "TO GET ANOTHER OUTPUT AS LISTED ABOVE TYPE 1,2 OR 3"
00640 PRINT
00645 PRINT "TYPE 4 IF YOU WOULD LIKE A TABLE OR GRAPH SHOWING"
00650 PRINT "THE LAUNCH VELOCITY NEEDED TO REACH CHOSEN HEIGHTS"
00655 PRINT
00660 PRINT "TYPE 0 TO END THE PROGRAM"
00665 INPUT A2
00670 PRINT
00675 PRINT
00680 IF A2=0 THEN 1165
00685 IF A2=1 THEN 170
00690 IF A2=2 THEN 265
00695 IF A2=2 THEN 505
00700 IF A2=4 THEN 725
00705 PRINT "REPLY WITH 0,1,2,3 OR 4"
00710 GOTO 665
00715 REM *****TABLE OR GRAPH OF LAUNCH VELOCITY NEEDED TO *****
00720 REM ***** REACH CHOSEN HEIGHTS *****
00725 PRINT "TYPE (1) FOR TABLE"
00730 PRINT " OR (2) FOR GRAPH"
00735 LET M1=1
00740 INPUT G1
00745 PRINT
00750 RESTORE
00755 IF (G1=1)*(G1-2)=0 THEN 765
00760 GOTO 725
00765 IF G1=2 THEN 925
00770 PRINT "TYPE (1) IF YOU WANT TO CHOOSE HEIGHTS YOURSELF"
00775 PRINT " OR (2) FOR VALUES STORED IN THE PROGRAM"
00780 INPUT D
00785 PRINT
00790 IF (D-1)*(D-2)=0 THEN 800
00795 GOTO 770
00800 PRINT
00805 IF D=2 THEN 865
00810 REM **TABLE ,OWN VALUES******
00815 GOSUB 1045
00820 PRINT "HEIGHT (METRES) LAUNCH VELOCITY(M,R)"
00825 PRINT "0 0"
00830 FOR H =H1 TO H9 STEP H1
00835 GOSUB 1190
00840 PRINT H1TAB(18);V
00845 NEXT H
00850 PRINT
00855 GOTO 995
00860 REM **TABLE,STORED VALUES ***
00865 PRINT "HEIGHT (METRES) LAUNCH VELOCITY(M/S)"
00870 PRINT
00875 GOSUB 1160
00880 PRINT
00885 PRINT "0
00890 FOR N=1 TO 14
00895 READ H
00900 GOSUB 1190
00905 PRINT H;TAB(10);V
00910 NEXT N
00915 GOTO 995
00920 REM **GRAPH ***
00925 GOSUB 1045
00930 PRINT
00935 PRINT " MT, LAUNCH VELOCITY(M/S)--------->"
00940 PRINT " (M) 0";TAB(63);V9
00945 PRINT " *---------*---------*---------*---------*";
00950 PRINT "---------*"
00955 LET F=1
00960 FOR H=H1 TO H9 STEP H1
00965 GOSUB 1190
00970 GOSUB 1125
00975 LET F=F*1
00980 NEXT H
00985 GOTO 995
00990 REM **RE-RUN QUERY **
00995 PRINT
01000 PRINT
01005 PRINT "TYPE 1 IF YOU WANT TO RE-RUN THIS PART OF THE PROGRAM"
01010 INPUT A3
01015 PRINT
01020 IF A3=1 THEN 725
01025 IF A3=0 THEN 1215
01030 PRINT "REPLY WITH 0 OR 1"
01035 GOTO 1010
01040 REM ***USER INPUTS HEIGHTS ***
01045 PRINT "TOTAL HEIGHT (METRES)=";
01050 INPUT M9
01055 IF M9>0 THEN 1065
01060 GOTO 1045
01065 LET M=M9
01070 GOSUB 1190
01075 LET M9=M
01080 LET V9=V
01085 PRINT
01090 LET M1=M9/10
01095 IF M1>=1000 THEN 1105
01100 GOSUB 1160
01105 PRINT
01110 PRINT
01115 RETURN
01120 REM ***GRAPH OUTPUT **
01125 FOR S=1 TO 4
01130 PRINT TAB(15);"*"
01135 NEXT S
01140 LET V=V*50/V9+9
01145 PRINT H=H1;TAB(15);"-";TAB(V);"*"
01150 RETURN
01155 REM ***WARNING ROUTINE***
01160 PRINT
01165 PRINT " WARNING : RESULTS MAY BE INACCURATE FOR HEIGHTS";
01170 PRINT " LAESS THAN 1000 M"
01175 PRINT
01180 PRINT
01185 LET E=K*H*P1/(R*R)
01195 LET V=SQR((E*E)/M1)
01200 RETURN
01205 DATA 1,10,100,1000,10000,100000,1E+6,1E+7,1E+8,1E+9
01210 DATA 1E+10,1E+11,1E+12,1E+13
01215 PRINT "END OF PROGRAM"
01220 END
