Home » Personal collection » Acorn ADFS disks » Electron_User_Group » EUG_55.ADF » V/+BTEAS4

V/+BTEAS4

This website contains an archive of files for the Acorn Electron, BBC Micro, Acorn Archimedes, Commodore 16 and Commodore 64 computers, which Dominic Ford has rescued from his private collection of floppy disks and cassettes.

Some of these files were originally commercial releases in the 1980s and 1990s, but they are now widely available online. I assume that copyright over them is no longer being asserted. If you own the copyright and would like files to be removed, please contact me.

Tape/disk: Home » Personal collection » Acorn ADFS disks » Electron_User_Group » EUG_55.ADF
Filename: V/+BTEAS4
Read OK:
File size: 1172 bytes
Load address: 2B204556
Exec address: 41455442
Duplicates

There are 3 duplicate copies of this file in the archive:

File contents
                             BRAINTEASERS
                            By G. Ludinski

WELCOME to the fourth article which supplements two programs on the 
'Arts' Menu (followed by "(BT)" in brackets). This issue presents DON'T
PAINT THE CAT and NAME THE GRAPH; fairly advanced playthings from Gene-
vieve Ludinski that are designed for ages 7+ and 11+ respectively. The
input procedures particularly on NAME THE GRAPH are cleverly orchestrat-
ed (Take a look at the code!) Note as usual that brief instructions 
appear on screen before each program.

DON'T PAINT THE CAT
SEEMS a strange title for a program. I mean, who would want to emulsion
paint the family mogg anyway?
   Well you see, the family have decided that you have to paint the gar-
den fence. You lost the draw - it might have been your sister instead 
who had to do it, but never mind, there's always next time. Across the
fence from you and your fantastic paint brush, is your neighbour's
transistor. As a mental challenge you have decided to paint the fence
according to the high/low pitch of your neighbour's music.
   Look out for your cat. It's parked at the end of the fence!

How to play
AS the game begins you will hear just two notes to compare but, every 
time you get the answer correct, the next tune will have an extra note.
   You will be told which two notes to compare, and you must input H or
L for High or Low.
   If you get it wrong, you must wait for the fence and the poor old 
pussy, to be painted. If you take too long to answer, the cat will wind
up getting covered in paint anyway.
   Press <RETURN> when you want a new tune.

Programming hints
IF you can work out the answer long before the cat is painted, then re-
duce the 50 of INKEY$(50) in line 350.
   If you find that it is too difficult to tell the difference between
the notes, then increase the 5 after the '*' sign in line 280.
   Alternatively you can increase the time allowed to answer, or reduce
the difference between the notes, by doing the opposite of what is des-
cribed above.

NAME THE GRAPH
THIS is a game of logic. You have an aim, to find the equation of the
graph that is drawn on the screen. You key in numbers to represent an
equation. You can see straight away whether you are getting closer to 
your goal as the graph of the equation you keyed in is drawn on the
screen.
   By making the three numbers required larger and smaller, postive and
negative, you can see how it effects the graph and hopefully, you can 
watch your graph getting closer and closer to the target graph until you
hit it.
   If you give up you will be told the answer, but don't cheat!

How to play
ALL graphs drawn are of the type:
      Y=Ax^2+Bx+C

where A, B and C are constants (that is, numbers that can be positive or
negative). For example, the equation might be:
      Y=-2x^2+3x-5

and in this case A would be equal to -2, B equal to 3 and C to -5.
   You must key in three numbers all at once on the same line and sepa-
rated by commas. Press <RETURN> only after you have keyed in all three
numbers. In the example above, you would key in:
      -2,3,-5 then <RETURN>

Then the graph of this expression is drawn and you must make another
guess. If you cannot guess the answer, key in:
      WHAT,IS,IT then <RETURN>

(remember to put in the commas) and you will be given the answer and the
program ends.
   If you guess the answer correctly then press <ESCAPE> and a new graph
will be drawn.
   It is more fun to find out how to do it by trial and error, but if
you want a hint then this is it. (Skip the next paragraph if you do not
want to know.)
   If the first number (A) is positive, then the graph will point up-
wards (u shape), and if it is negative, the graph will point downwards 
(n shape).

Programming hints
THE graphs are plotted with the origin (zero, zero point) at the middle
of the screen by using the VDU statement in line 50. This saves a lot of
unnecessary maths.
   You could make the programs easier by reducing the range of the num-
bers allowed. Do this by reducing the 5 in line 280 or the 9 in line 290
or both. If you want to make it very easy you can allow only positive 
numbers by deleting line 300.
   The program uses Mode 1 to enable guessed graphs to be displayed in 
red, and the target graph in white. On a BBC Model A, you will need to 
change line 40 to Mode 1. The program then runs without colour.
                                             Genevieve Ludinski, EUG #55
00000000  20 20 20 20 20 20 20 20  20 20 20 20 20 20 20 20  |                |
00000010  20 20 20 20 20 20 20 20  20 20 20 20 20 42 52 41  |             BRA|
00000020  49 4e 54 45 41 53 45 52  53 0d 20 20 20 20 20 20  |INTEASERS.      |
00000030  20 20 20 20 20 20 20 20  20 20 20 20 20 20 20 20  |                |
00000040  20 20 20 20 20 20 42 79  20 47 2e 20 4c 75 64 69  |      By G. Ludi|
00000050  6e 73 6b 69 0d 0d 57 45  4c 43 4f 4d 45 20 74 6f  |nski..WELCOME to|
00000060  20 74 68 65 20 66 6f 75  72 74 68 20 61 72 74 69  | the fourth arti|
00000070  63 6c 65 20 77 68 69 63  68 20 73 75 70 70 6c 65  |cle which supple|
00000080  6d 65 6e 74 73 20 74 77  6f 20 70 72 6f 67 72 61  |ments two progra|
00000090  6d 73 20 6f 6e 20 74 68  65 20 0d 27 41 72 74 73  |ms on the .'Arts|
000000a0  27 20 4d 65 6e 75 20 28  66 6f 6c 6c 6f 77 65 64  |' Menu (followed|
000000b0  20 62 79 20 22 28 42 54  29 22 20 69 6e 20 62 72  | by "(BT)" in br|
000000c0  61 63 6b 65 74 73 29 2e  20 54 68 69 73 20 69 73  |ackets). This is|
000000d0  73 75 65 20 70 72 65 73  65 6e 74 73 20 44 4f 4e  |sue presents DON|
000000e0  27 54 0d 50 41 49 4e 54  20 54 48 45 20 43 41 54  |'T.PAINT THE CAT|
000000f0  20 61 6e 64 20 4e 41 4d  45 20 54 48 45 20 47 52  | and NAME THE GR|
00000100  41 50 48 3b 20 66 61 69  72 6c 79 20 61 64 76 61  |APH; fairly adva|
00000110  6e 63 65 64 20 70 6c 61  79 74 68 69 6e 67 73 20  |nced playthings |
00000120  66 72 6f 6d 20 47 65 6e  65 2d 0d 76 69 65 76 65  |from Gene-.vieve|
00000130  20 4c 75 64 69 6e 73 6b  69 20 74 68 61 74 20 61  | Ludinski that a|
00000140  72 65 20 64 65 73 69 67  6e 65 64 20 66 6f 72 20  |re designed for |
00000150  61 67 65 73 20 37 2b 20  61 6e 64 20 31 31 2b 20  |ages 7+ and 11+ |
00000160  72 65 73 70 65 63 74 69  76 65 6c 79 2e 20 54 68  |respectively. Th|
00000170  65 0d 69 6e 70 75 74 20  70 72 6f 63 65 64 75 72  |e.input procedur|
00000180  65 73 20 70 61 72 74 69  63 75 6c 61 72 6c 79 20  |es particularly |
00000190  6f 6e 20 4e 41 4d 45 20  54 48 45 20 47 52 41 50  |on NAME THE GRAP|
000001a0  48 20 61 72 65 20 63 6c  65 76 65 72 6c 79 20 6f  |H are cleverly o|
000001b0  72 63 68 65 73 74 72 61  74 2d 0d 65 64 20 28 54  |rchestrat-.ed (T|
000001c0  61 6b 65 20 61 20 6c 6f  6f 6b 20 61 74 20 74 68  |ake a look at th|
000001d0  65 20 63 6f 64 65 21 29  20 4e 6f 74 65 20 61 73  |e code!) Note as|
000001e0  20 75 73 75 61 6c 20 74  68 61 74 20 62 72 69 65  | usual that brie|
000001f0  66 20 69 6e 73 74 72 75  63 74 69 6f 6e 73 20 0d  |f instructions .|
00000200  61 70 70 65 61 72 20 6f  6e 20 73 63 72 65 65 6e  |appear on screen|
00000210  20 62 65 66 6f 72 65 20  65 61 63 68 20 70 72 6f  | before each pro|
00000220  67 72 61 6d 2e 0d 0d 44  4f 4e 27 54 20 50 41 49  |gram...DON'T PAI|
00000230  4e 54 20 54 48 45 20 43  41 54 0d 53 45 45 4d 53  |NT THE CAT.SEEMS|
00000240  20 61 20 73 74 72 61 6e  67 65 20 74 69 74 6c 65  | a strange title|
00000250  20 66 6f 72 20 61 20 70  72 6f 67 72 61 6d 2e 20  | for a program. |
00000260  49 20 6d 65 61 6e 2c 20  77 68 6f 20 77 6f 75 6c  |I mean, who woul|
00000270  64 20 77 61 6e 74 20 74  6f 20 65 6d 75 6c 73 69  |d want to emulsi|
00000280  6f 6e 0d 70 61 69 6e 74  20 74 68 65 20 66 61 6d  |on.paint the fam|
00000290  69 6c 79 20 6d 6f 67 67  20 61 6e 79 77 61 79 3f  |ily mogg anyway?|
000002a0  0d 20 20 20 57 65 6c 6c  20 79 6f 75 20 73 65 65  |.   Well you see|
000002b0  2c 20 74 68 65 20 66 61  6d 69 6c 79 20 68 61 76  |, the family hav|
000002c0  65 20 64 65 63 69 64 65  64 20 74 68 61 74 20 79  |e decided that y|
000002d0  6f 75 20 68 61 76 65 20  74 6f 20 70 61 69 6e 74  |ou have to paint|
000002e0  20 74 68 65 20 67 61 72  2d 0d 64 65 6e 20 66 65  | the gar-.den fe|
000002f0  6e 63 65 2e 20 59 6f 75  20 6c 6f 73 74 20 74 68  |nce. You lost th|
00000300  65 20 64 72 61 77 20 2d  20 69 74 20 6d 69 67 68  |e draw - it migh|
00000310  74 20 68 61 76 65 20 62  65 65 6e 20 79 6f 75 72  |t have been your|
00000320  20 73 69 73 74 65 72 20  69 6e 73 74 65 61 64 20  | sister instead |
00000330  0d 77 68 6f 20 68 61 64  20 74 6f 20 64 6f 20 69  |.who had to do i|
00000340  74 2c 20 62 75 74 20 6e  65 76 65 72 20 6d 69 6e  |t, but never min|
00000350  64 2c 20 74 68 65 72 65  27 73 20 61 6c 77 61 79  |d, there's alway|
00000360  73 20 6e 65 78 74 20 74  69 6d 65 2e 20 41 63 72  |s next time. Acr|
00000370  6f 73 73 20 74 68 65 0d  66 65 6e 63 65 20 66 72  |oss the.fence fr|
00000380  6f 6d 20 79 6f 75 20 61  6e 64 20 79 6f 75 72 20  |om you and your |
00000390  66 61 6e 74 61 73 74 69  63 20 70 61 69 6e 74 20  |fantastic paint |
000003a0  62 72 75 73 68 2c 20 69  73 20 79 6f 75 72 20 6e  |brush, is your n|
000003b0  65 69 67 68 62 6f 75 72  27 73 0d 74 72 61 6e 73  |eighbour's.trans|
000003c0  69 73 74 6f 72 2e 20 41  73 20 61 20 6d 65 6e 74  |istor. As a ment|
000003d0  61 6c 20 63 68 61 6c 6c  65 6e 67 65 20 79 6f 75  |al challenge you|
000003e0  20 68 61 76 65 20 64 65  63 69 64 65 64 20 74 6f  | have decided to|
000003f0  20 70 61 69 6e 74 20 74  68 65 20 66 65 6e 63 65  | paint the fence|
00000400  0d 61 63 63 6f 72 64 69  6e 67 20 74 6f 20 74 68  |.according to th|
00000410  65 20 68 69 67 68 2f 6c  6f 77 20 70 69 74 63 68  |e high/low pitch|
00000420  20 6f 66 20 79 6f 75 72  20 6e 65 69 67 68 62 6f  | of your neighbo|
00000430  75 72 27 73 20 6d 75 73  69 63 2e 0d 20 20 20 4c  |ur's music..   L|
00000440  6f 6f 6b 20 6f 75 74 20  66 6f 72 20 79 6f 75 72  |ook out for your|
00000450  20 63 61 74 2e 20 49 74  27 73 20 70 61 72 6b 65  | cat. It's parke|
00000460  64 20 61 74 20 74 68 65  20 65 6e 64 20 6f 66 20  |d at the end of |
00000470  74 68 65 20 66 65 6e 63  65 21 0d 0d 48 6f 77 20  |the fence!..How |
00000480  74 6f 20 70 6c 61 79 0d  41 53 20 74 68 65 20 67  |to play.AS the g|
00000490  61 6d 65 20 62 65 67 69  6e 73 20 79 6f 75 20 77  |ame begins you w|
000004a0  69 6c 6c 20 68 65 61 72  20 6a 75 73 74 20 74 77  |ill hear just tw|
000004b0  6f 20 6e 6f 74 65 73 20  74 6f 20 63 6f 6d 70 61  |o notes to compa|
000004c0  72 65 20 62 75 74 2c 20  65 76 65 72 79 20 0d 74  |re but, every .t|
000004d0  69 6d 65 20 79 6f 75 20  67 65 74 20 74 68 65 20  |ime you get the |
000004e0  61 6e 73 77 65 72 20 63  6f 72 72 65 63 74 2c 20  |answer correct, |
000004f0  74 68 65 20 6e 65 78 74  20 74 75 6e 65 20 77 69  |the next tune wi|
00000500  6c 6c 20 68 61 76 65 20  61 6e 20 65 78 74 72 61  |ll have an extra|
00000510  20 6e 6f 74 65 2e 0d 20  20 20 59 6f 75 20 77 69  | note..   You wi|
00000520  6c 6c 20 62 65 20 74 6f  6c 64 20 77 68 69 63 68  |ll be told which|
00000530  20 74 77 6f 20 6e 6f 74  65 73 20 74 6f 20 63 6f  | two notes to co|
00000540  6d 70 61 72 65 2c 20 61  6e 64 20 79 6f 75 20 6d  |mpare, and you m|
00000550  75 73 74 20 69 6e 70 75  74 20 48 20 6f 72 0d 4c  |ust input H or.L|
00000560  20 66 6f 72 20 48 69 67  68 20 6f 72 20 4c 6f 77  | for High or Low|
00000570  2e 0d 20 20 20 49 66 20  79 6f 75 20 67 65 74 20  |..   If you get |
00000580  69 74 20 77 72 6f 6e 67  2c 20 79 6f 75 20 6d 75  |it wrong, you mu|
00000590  73 74 20 77 61 69 74 20  66 6f 72 20 74 68 65 20  |st wait for the |
000005a0  66 65 6e 63 65 20 61 6e  64 20 74 68 65 20 70 6f  |fence and the po|
000005b0  6f 72 20 6f 6c 64 20 0d  70 75 73 73 79 2c 20 74  |or old .pussy, t|
000005c0  6f 20 62 65 20 70 61 69  6e 74 65 64 2e 20 49 66  |o be painted. If|
000005d0  20 79 6f 75 20 74 61 6b  65 20 74 6f 6f 20 6c 6f  | you take too lo|
000005e0  6e 67 20 74 6f 20 61 6e  73 77 65 72 2c 20 74 68  |ng to answer, th|
000005f0  65 20 63 61 74 20 77 69  6c 6c 20 77 69 6e 64 0d  |e cat will wind.|
00000600  75 70 20 67 65 74 74 69  6e 67 20 63 6f 76 65 72  |up getting cover|
00000610  65 64 20 69 6e 20 70 61  69 6e 74 20 61 6e 79 77  |ed in paint anyw|
00000620  61 79 2e 0d 20 20 20 50  72 65 73 73 20 3c 52 45  |ay..   Press <RE|
00000630  54 55 52 4e 3e 20 77 68  65 6e 20 79 6f 75 20 77  |TURN> when you w|
00000640  61 6e 74 20 61 20 6e 65  77 20 74 75 6e 65 2e 0d  |ant a new tune..|
00000650  0d 50 72 6f 67 72 61 6d  6d 69 6e 67 20 68 69 6e  |.Programming hin|
00000660  74 73 0d 49 46 20 79 6f  75 20 63 61 6e 20 77 6f  |ts.IF you can wo|
00000670  72 6b 20 6f 75 74 20 74  68 65 20 61 6e 73 77 65  |rk out the answe|
00000680  72 20 6c 6f 6e 67 20 62  65 66 6f 72 65 20 74 68  |r long before th|
00000690  65 20 63 61 74 20 69 73  20 70 61 69 6e 74 65 64  |e cat is painted|
000006a0  2c 20 74 68 65 6e 20 72  65 2d 0d 64 75 63 65 20  |, then re-.duce |
000006b0  74 68 65 20 35 30 20 6f  66 20 49 4e 4b 45 59 24  |the 50 of INKEY$|
000006c0  28 35 30 29 20 69 6e 20  6c 69 6e 65 20 33 35 30  |(50) in line 350|
000006d0  2e 0d 20 20 20 49 66 20  79 6f 75 20 66 69 6e 64  |..   If you find|
000006e0  20 74 68 61 74 20 69 74  20 69 73 20 74 6f 6f 20  | that it is too |
000006f0  64 69 66 66 69 63 75 6c  74 20 74 6f 20 74 65 6c  |difficult to tel|
00000700  6c 20 74 68 65 20 64 69  66 66 65 72 65 6e 63 65  |l the difference|
00000710  20 62 65 74 77 65 65 6e  0d 74 68 65 20 6e 6f 74  | between.the not|
00000720  65 73 2c 20 74 68 65 6e  20 69 6e 63 72 65 61 73  |es, then increas|
00000730  65 20 74 68 65 20 35 20  61 66 74 65 72 20 74 68  |e the 5 after th|
00000740  65 20 27 2a 27 20 73 69  67 6e 20 69 6e 20 6c 69  |e '*' sign in li|
00000750  6e 65 20 32 38 30 2e 0d  20 20 20 41 6c 74 65 72  |ne 280..   Alter|
00000760  6e 61 74 69 76 65 6c 79  20 79 6f 75 20 63 61 6e  |natively you can|
00000770  20 69 6e 63 72 65 61 73  65 20 74 68 65 20 74 69  | increase the ti|
00000780  6d 65 20 61 6c 6c 6f 77  65 64 20 74 6f 20 61 6e  |me allowed to an|
00000790  73 77 65 72 2c 20 6f 72  20 72 65 64 75 63 65 0d  |swer, or reduce.|
000007a0  74 68 65 20 64 69 66 66  65 72 65 6e 63 65 20 62  |the difference b|
000007b0  65 74 77 65 65 6e 20 74  68 65 20 6e 6f 74 65 73  |etween the notes|
000007c0  2c 20 62 79 20 64 6f 69  6e 67 20 74 68 65 20 6f  |, by doing the o|
000007d0  70 70 6f 73 69 74 65 20  6f 66 20 77 68 61 74 20  |pposite of what |
000007e0  69 73 20 64 65 73 2d 0d  63 72 69 62 65 64 20 61  |is des-.cribed a|
000007f0  62 6f 76 65 2e 0d 0d 4e  41 4d 45 20 54 48 45 20  |bove...NAME THE |
00000800  47 52 41 50 48 0d 54 48  49 53 20 69 73 20 61 20  |GRAPH.THIS is a |
00000810  67 61 6d 65 20 6f 66 20  6c 6f 67 69 63 2e 20 59  |game of logic. Y|
00000820  6f 75 20 68 61 76 65 20  61 6e 20 61 69 6d 2c 20  |ou have an aim, |
00000830  74 6f 20 66 69 6e 64 20  74 68 65 20 65 71 75 61  |to find the equa|
00000840  74 69 6f 6e 20 6f 66 20  74 68 65 0d 67 72 61 70  |tion of the.grap|
00000850  68 20 74 68 61 74 20 69  73 20 64 72 61 77 6e 20  |h that is drawn |
00000860  6f 6e 20 74 68 65 20 73  63 72 65 65 6e 2e 20 59  |on the screen. Y|
00000870  6f 75 20 6b 65 79 20 69  6e 20 6e 75 6d 62 65 72  |ou key in number|
00000880  73 20 74 6f 20 72 65 70  72 65 73 65 6e 74 20 61  |s to represent a|
00000890  6e 0d 65 71 75 61 74 69  6f 6e 2e 20 59 6f 75 20  |n.equation. You |
000008a0  63 61 6e 20 73 65 65 20  73 74 72 61 69 67 68 74  |can see straight|
000008b0  20 61 77 61 79 20 77 68  65 74 68 65 72 20 79 6f  | away whether yo|
000008c0  75 20 61 72 65 20 67 65  74 74 69 6e 67 20 63 6c  |u are getting cl|
000008d0  6f 73 65 72 20 74 6f 20  0d 79 6f 75 72 20 67 6f  |oser to .your go|
000008e0  61 6c 20 61 73 20 74 68  65 20 67 72 61 70 68 20  |al as the graph |
000008f0  6f 66 20 74 68 65 20 65  71 75 61 74 69 6f 6e 20  |of the equation |
00000900  79 6f 75 20 6b 65 79 65  64 20 69 6e 20 69 73 20  |you keyed in is |
00000910  64 72 61 77 6e 20 6f 6e  20 74 68 65 0d 73 63 72  |drawn on the.scr|
00000920  65 65 6e 2e 0d 20 20 20  42 79 20 6d 61 6b 69 6e  |een..   By makin|
00000930  67 20 74 68 65 20 74 68  72 65 65 20 6e 75 6d 62  |g the three numb|
00000940  65 72 73 20 72 65 71 75  69 72 65 64 20 6c 61 72  |ers required lar|
00000950  67 65 72 20 61 6e 64 20  73 6d 61 6c 6c 65 72 2c  |ger and smaller,|
00000960  20 70 6f 73 74 69 76 65  20 61 6e 64 0d 6e 65 67  | postive and.neg|
00000970  61 74 69 76 65 2c 20 79  6f 75 20 63 61 6e 20 73  |ative, you can s|
00000980  65 65 20 68 6f 77 20 69  74 20 65 66 66 65 63 74  |ee how it effect|
00000990  73 20 74 68 65 20 67 72  61 70 68 20 61 6e 64 20  |s the graph and |
000009a0  68 6f 70 65 66 75 6c 6c  79 2c 20 79 6f 75 20 63  |hopefully, you c|
000009b0  61 6e 20 0d 77 61 74 63  68 20 79 6f 75 72 20 67  |an .watch your g|
000009c0  72 61 70 68 20 67 65 74  74 69 6e 67 20 63 6c 6f  |raph getting clo|
000009d0  73 65 72 20 61 6e 64 20  63 6c 6f 73 65 72 20 74  |ser and closer t|
000009e0  6f 20 74 68 65 20 74 61  72 67 65 74 20 67 72 61  |o the target gra|
000009f0  70 68 20 75 6e 74 69 6c  20 79 6f 75 0d 68 69 74  |ph until you.hit|
00000a00  20 69 74 2e 0d 20 20 20  49 66 20 79 6f 75 20 67  | it..   If you g|
00000a10  69 76 65 20 75 70 20 79  6f 75 20 77 69 6c 6c 20  |ive up you will |
00000a20  62 65 20 74 6f 6c 64 20  74 68 65 20 61 6e 73 77  |be told the answ|
00000a30  65 72 2c 20 62 75 74 20  64 6f 6e 27 74 20 63 68  |er, but don't ch|
00000a40  65 61 74 21 0d 0d 48 6f  77 20 74 6f 20 70 6c 61  |eat!..How to pla|
00000a50  79 0d 41 4c 4c 20 67 72  61 70 68 73 20 64 72 61  |y.ALL graphs dra|
00000a60  77 6e 20 61 72 65 20 6f  66 20 74 68 65 20 74 79  |wn are of the ty|
00000a70  70 65 3a 0d 20 20 20 20  20 20 59 3d 41 78 5e 32  |pe:.      Y=Ax^2|
00000a80  2b 42 78 2b 43 0d 0d 77  68 65 72 65 20 41 2c 20  |+Bx+C..where A, |
00000a90  42 20 61 6e 64 20 43 20  61 72 65 20 63 6f 6e 73  |B and C are cons|
00000aa0  74 61 6e 74 73 20 28 74  68 61 74 20 69 73 2c 20  |tants (that is, |
00000ab0  6e 75 6d 62 65 72 73 20  74 68 61 74 20 63 61 6e  |numbers that can|
00000ac0  20 62 65 20 70 6f 73 69  74 69 76 65 20 6f 72 0d  | be positive or.|
00000ad0  6e 65 67 61 74 69 76 65  29 2e 20 46 6f 72 20 65  |negative). For e|
00000ae0  78 61 6d 70 6c 65 2c 20  74 68 65 20 65 71 75 61  |xample, the equa|
00000af0  74 69 6f 6e 20 6d 69 67  68 74 20 62 65 3a 0d 20  |tion might be:. |
00000b00  20 20 20 20 20 59 3d 2d  32 78 5e 32 2b 33 78 2d  |     Y=-2x^2+3x-|
00000b10  35 0d 0d 61 6e 64 20 69  6e 20 74 68 69 73 20 63  |5..and in this c|
00000b20  61 73 65 20 41 20 77 6f  75 6c 64 20 62 65 20 65  |ase A would be e|
00000b30  71 75 61 6c 20 74 6f 20  2d 32 2c 20 42 20 65 71  |qual to -2, B eq|
00000b40  75 61 6c 20 74 6f 20 33  20 61 6e 64 20 43 20 74  |ual to 3 and C t|
00000b50  6f 20 2d 35 2e 0d 20 20  20 59 6f 75 20 6d 75 73  |o -5..   You mus|
00000b60  74 20 6b 65 79 20 69 6e  20 74 68 72 65 65 20 6e  |t key in three n|
00000b70  75 6d 62 65 72 73 20 61  6c 6c 20 61 74 20 6f 6e  |umbers all at on|
00000b80  63 65 20 6f 6e 20 74 68  65 20 73 61 6d 65 20 6c  |ce on the same l|
00000b90  69 6e 65 20 61 6e 64 20  73 65 70 61 2d 0d 72 61  |ine and sepa-.ra|
00000ba0  74 65 64 20 62 79 20 63  6f 6d 6d 61 73 2e 20 50  |ted by commas. P|
00000bb0  72 65 73 73 20 3c 52 45  54 55 52 4e 3e 20 6f 6e  |ress <RETURN> on|
00000bc0  6c 79 20 61 66 74 65 72  20 79 6f 75 20 68 61 76  |ly after you hav|
00000bd0  65 20 6b 65 79 65 64 20  69 6e 20 61 6c 6c 20 74  |e keyed in all t|
00000be0  68 72 65 65 0d 6e 75 6d  62 65 72 73 2e 20 49 6e  |hree.numbers. In|
00000bf0  20 74 68 65 20 65 78 61  6d 70 6c 65 20 61 62 6f  | the example abo|
00000c00  76 65 2c 20 79 6f 75 20  77 6f 75 6c 64 20 6b 65  |ve, you would ke|
00000c10  79 20 69 6e 3a 0d 20 20  20 20 20 20 2d 32 2c 33  |y in:.      -2,3|
00000c20  2c 2d 35 20 74 68 65 6e  20 3c 52 45 54 55 52 4e  |,-5 then <RETURN|
00000c30  3e 0d 0d 54 68 65 6e 20  74 68 65 20 67 72 61 70  |>..Then the grap|
00000c40  68 20 6f 66 20 74 68 69  73 20 65 78 70 72 65 73  |h of this expres|
00000c50  73 69 6f 6e 20 69 73 20  64 72 61 77 6e 20 61 6e  |sion is drawn an|
00000c60  64 20 79 6f 75 20 6d 75  73 74 20 6d 61 6b 65 20  |d you must make |
00000c70  61 6e 6f 74 68 65 72 0d  67 75 65 73 73 2e 20 49  |another.guess. I|
00000c80  66 20 79 6f 75 20 63 61  6e 6e 6f 74 20 67 75 65  |f you cannot gue|
00000c90  73 73 20 74 68 65 20 61  6e 73 77 65 72 2c 20 6b  |ss the answer, k|
00000ca0  65 79 20 69 6e 3a 0d 20  20 20 20 20 20 57 48 41  |ey in:.      WHA|
00000cb0  54 2c 49 53 2c 49 54 20  74 68 65 6e 20 3c 52 45  |T,IS,IT then <RE|
00000cc0  54 55 52 4e 3e 0d 0d 28  72 65 6d 65 6d 62 65 72  |TURN>..(remember|
00000cd0  20 74 6f 20 70 75 74 20  69 6e 20 74 68 65 20 63  | to put in the c|
00000ce0  6f 6d 6d 61 73 29 20 61  6e 64 20 79 6f 75 20 77  |ommas) and you w|
00000cf0  69 6c 6c 20 62 65 20 67  69 76 65 6e 20 74 68 65  |ill be given the|
00000d00  20 61 6e 73 77 65 72 20  61 6e 64 20 74 68 65 0d  | answer and the.|
00000d10  70 72 6f 67 72 61 6d 20  65 6e 64 73 2e 0d 20 20  |program ends..  |
00000d20  20 49 66 20 79 6f 75 20  67 75 65 73 73 20 74 68  | If you guess th|
00000d30  65 20 61 6e 73 77 65 72  20 63 6f 72 72 65 63 74  |e answer correct|
00000d40  6c 79 20 74 68 65 6e 20  70 72 65 73 73 20 3c 45  |ly then press <E|
00000d50  53 43 41 50 45 3e 20 61  6e 64 20 61 20 6e 65 77  |SCAPE> and a new|
00000d60  20 67 72 61 70 68 0d 77  69 6c 6c 20 62 65 20 64  | graph.will be d|
00000d70  72 61 77 6e 2e 0d 20 20  20 49 74 20 69 73 20 6d  |rawn..   It is m|
00000d80  6f 72 65 20 66 75 6e 20  74 6f 20 66 69 6e 64 20  |ore fun to find |
00000d90  6f 75 74 20 68 6f 77 20  74 6f 20 64 6f 20 69 74  |out how to do it|
00000da0  20 62 79 20 74 72 69 61  6c 20 61 6e 64 20 65 72  | by trial and er|
00000db0  72 6f 72 2c 20 62 75 74  20 69 66 0d 79 6f 75 20  |ror, but if.you |
00000dc0  77 61 6e 74 20 61 20 68  69 6e 74 20 74 68 65 6e  |want a hint then|
00000dd0  20 74 68 69 73 20 69 73  20 69 74 2e 20 28 53 6b  | this is it. (Sk|
00000de0  69 70 20 74 68 65 20 6e  65 78 74 20 70 61 72 61  |ip the next para|
00000df0  67 72 61 70 68 20 69 66  20 79 6f 75 20 64 6f 20  |graph if you do |
00000e00  6e 6f 74 0d 77 61 6e 74  20 74 6f 20 6b 6e 6f 77  |not.want to know|
00000e10  2e 29 0d 20 20 20 49 66  20 74 68 65 20 66 69 72  |.).   If the fir|
00000e20  73 74 20 6e 75 6d 62 65  72 20 28 41 29 20 69 73  |st number (A) is|
00000e30  20 70 6f 73 69 74 69 76  65 2c 20 74 68 65 6e 20  | positive, then |
00000e40  74 68 65 20 67 72 61 70  68 20 77 69 6c 6c 20 70  |the graph will p|
00000e50  6f 69 6e 74 20 75 70 2d  0d 77 61 72 64 73 20 28  |oint up-.wards (|
00000e60  75 20 73 68 61 70 65 29  2c 20 61 6e 64 20 69 66  |u shape), and if|
00000e70  20 69 74 20 69 73 20 6e  65 67 61 74 69 76 65 2c  | it is negative,|
00000e80  20 74 68 65 20 67 72 61  70 68 20 77 69 6c 6c 20  | the graph will |
00000e90  70 6f 69 6e 74 20 64 6f  77 6e 77 61 72 64 73 20  |point downwards |
00000ea0  0d 28 6e 20 73 68 61 70  65 29 2e 0d 0d 50 72 6f  |.(n shape)...Pro|
00000eb0  67 72 61 6d 6d 69 6e 67  20 68 69 6e 74 73 0d 54  |gramming hints.T|
00000ec0  48 45 20 67 72 61 70 68  73 20 61 72 65 20 70 6c  |HE graphs are pl|
00000ed0  6f 74 74 65 64 20 77 69  74 68 20 74 68 65 20 6f  |otted with the o|
00000ee0  72 69 67 69 6e 20 28 7a  65 72 6f 2c 20 7a 65 72  |rigin (zero, zer|
00000ef0  6f 20 70 6f 69 6e 74 29  20 61 74 20 74 68 65 20  |o point) at the |
00000f00  6d 69 64 64 6c 65 0d 6f  66 20 74 68 65 20 73 63  |middle.of the sc|
00000f10  72 65 65 6e 20 62 79 20  75 73 69 6e 67 20 74 68  |reen by using th|
00000f20  65 20 56 44 55 20 73 74  61 74 65 6d 65 6e 74 20  |e VDU statement |
00000f30  69 6e 20 6c 69 6e 65 20  35 30 2e 20 54 68 69 73  |in line 50. This|
00000f40  20 73 61 76 65 73 20 61  20 6c 6f 74 20 6f 66 0d  | saves a lot of.|
00000f50  75 6e 6e 65 63 65 73 73  61 72 79 20 6d 61 74 68  |unnecessary math|
00000f60  73 2e 0d 20 20 20 59 6f  75 20 63 6f 75 6c 64 20  |s..   You could |
00000f70  6d 61 6b 65 20 74 68 65  20 70 72 6f 67 72 61 6d  |make the program|
00000f80  73 20 65 61 73 69 65 72  20 62 79 20 72 65 64 75  |s easier by redu|
00000f90  63 69 6e 67 20 74 68 65  20 72 61 6e 67 65 20 6f  |cing the range o|
00000fa0  66 20 74 68 65 20 6e 75  6d 2d 0d 62 65 72 73 20  |f the num-.bers |
00000fb0  61 6c 6c 6f 77 65 64 2e  20 44 6f 20 74 68 69 73  |allowed. Do this|
00000fc0  20 62 79 20 72 65 64 75  63 69 6e 67 20 74 68 65  | by reducing the|
00000fd0  20 35 20 69 6e 20 6c 69  6e 65 20 32 38 30 20 6f  | 5 in line 280 o|
00000fe0  72 20 74 68 65 20 39 20  69 6e 20 6c 69 6e 65 20  |r the 9 in line |
00000ff0  32 39 30 0d 6f 72 20 62  6f 74 68 2e 20 49 66 20  |290.or both. If |
00001000  79 6f 75 20 77 61 6e 74  20 74 6f 20 6d 61 6b 65  |you want to make|
00001010  20 69 74 20 76 65 72 79  20 65 61 73 79 20 79 6f  | it very easy yo|
00001020  75 20 63 61 6e 20 61 6c  6c 6f 77 20 6f 6e 6c 79  |u can allow only|
00001030  20 70 6f 73 69 74 69 76  65 20 0d 6e 75 6d 62 65  | positive .numbe|
00001040  72 73 20 62 79 20 64 65  6c 65 74 69 6e 67 20 6c  |rs by deleting l|
00001050  69 6e 65 20 33 30 30 2e  0d 20 20 20 54 68 65 20  |ine 300..   The |
00001060  70 72 6f 67 72 61 6d 20  75 73 65 73 20 4d 6f 64  |program uses Mod|
00001070  65 20 31 20 74 6f 20 65  6e 61 62 6c 65 20 67 75  |e 1 to enable gu|
00001080  65 73 73 65 64 20 67 72  61 70 68 73 20 74 6f 20  |essed graphs to |
00001090  62 65 20 64 69 73 70 6c  61 79 65 64 20 69 6e 20  |be displayed in |
000010a0  0d 72 65 64 2c 20 61 6e  64 20 74 68 65 20 74 61  |.red, and the ta|
000010b0  72 67 65 74 20 67 72 61  70 68 20 69 6e 20 77 68  |rget graph in wh|
000010c0  69 74 65 2e 20 4f 6e 20  61 20 42 42 43 20 4d 6f  |ite. On a BBC Mo|
000010d0  64 65 6c 20 41 2c 20 79  6f 75 20 77 69 6c 6c 20  |del A, you will |
000010e0  6e 65 65 64 20 74 6f 20  0d 63 68 61 6e 67 65 20  |need to .change |
000010f0  6c 69 6e 65 20 34 30 20  74 6f 20 4d 6f 64 65 20  |line 40 to Mode |
00001100  31 2e 20 54 68 65 20 70  72 6f 67 72 61 6d 20 74  |1. The program t|
00001110  68 65 6e 20 72 75 6e 73  20 77 69 74 68 6f 75 74  |hen runs without|
00001120  20 63 6f 6c 6f 75 72 2e  0d 20 20 20 20 20 20 20  | colour..       |
00001130  20 20 20 20 20 20 20 20  20 20 20 20 20 20 20 20  |                |
*
00001150  20 20 20 20 20 20 47 65  6e 65 76 69 65 76 65 20  |      Genevieve |
00001160  4c 75 64 69 6e 73 6b 69  2c 20 45 55 47 20 23 35  |Ludinski, EUG #5|
00001170  35 0d                                             |5.|
00001172
V/+BTEAS4.m0
V/+BTEAS4.m1
V/+BTEAS4.m2
V/+BTEAS4.m4
V/+BTEAS4.m5