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!AWMar92/Goodies/ArcAut/Info/Table4
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| Filename: | !AWMar92/Goodies/ArcAut/Info/Table4 |
| Read OK: | ✔ |
| File size: | 0DBD bytes |
| Load address: | 0000 |
| Exec address: | 0000 |
File contents
TABLE 4: Initialisation of parameters
There is an as yet unresolved problem concerning what happens at the edge of the CA universe, where cells apparently don't
always have the full complement of neighbours.
ArcAut allows two solutions. We can either identify the left hand edge with the right hand edge, as if they were side by side,
& similarly, the top with the bottom. The result is that we no longer have any edges to worry about! The window effectively
corresponds to the surface of a torus or doughnut (the sort with a hole in the middle). The other possibility is to let the
automaton behave as if the border of cells surrounding the window do exist, but are forced to maintain a fixed state. This is
used in the current definition of 'Life'. It is a useful facility if we want to prevent 'objects' such as gliders, wandering off one side of the window, only to reappear on the other, & then go & interfere with whatever is happening in the centre.
Name of system variable Possible values Default value Meaning
wrap on|off on selects whether the CA universe has wrap-around or
is bordered by cells of a fixed state
border {0,1,. . .,255} no default specifies cell state for border; used when wrap=off
neig moore|margolus moore selects the type of neighbourhood required by the
automaton; see table 3
flag 0|3|4|7 0 used when neig=margolus; specifies whether automaton
code register FLAG should return:
0 ;if flag=0
0|1|2|3 depending on CELL's position within block
0 for UL, 1 for UR, 2 for LL, 3 for LR ;if flag=3
0|4 depending on the phase
0 for even phase, 4 for odd phase ;if flag=4
0 to 7 the sum of the above two items ;if flag=7
see table 3
rndb on|off off when neig=margolus & automaton requires use of the
RNDB command, you must set rndb to on;
see tables 2 & 3 and example DLA automaton
To set any of these values include a command, for example '*SetEval wrap off', within the body of the procedure called do, in
the section of text between INITIALISATION* & SCREEN* ; see some of the automatons provided for examples.
You may also use this procedure to allow the user to input parameters needed by your automaton; note, these must also be passed to the rest of the automaton via system variables. See for example the automatons Demon & FracGrow. 00000000 0a 20 54 41 42 4c 45 20 34 3a 20 49 6e 69 74 69 |. TABLE 4: Initi|
00000010 61 6c 69 73 61 74 69 6f 6e 20 6f 66 20 70 61 72 |alisation of par|
00000020 61 6d 65 74 65 72 73 0a 0a 0a 20 20 54 68 65 72 |ameters... Ther|
00000030 65 20 69 73 20 61 6e 20 61 73 20 79 65 74 20 75 |e is an as yet u|
00000040 6e 72 65 73 6f 6c 76 65 64 20 70 72 6f 62 6c 65 |nresolved proble|
00000050 6d 20 63 6f 6e 63 65 72 6e 69 6e 67 20 77 68 61 |m concerning wha|
00000060 74 20 68 61 70 70 65 6e 73 20 61 74 20 74 68 65 |t happens at the|
00000070 20 65 64 67 65 20 6f 66 20 74 68 65 20 43 41 20 | edge of the CA |
00000080 75 6e 69 76 65 72 73 65 2c 20 77 68 65 72 65 20 |universe, where |
00000090 63 65 6c 6c 73 20 61 70 70 61 72 65 6e 74 6c 79 |cells apparently|
000000a0 20 64 6f 6e 27 74 0a 61 6c 77 61 79 73 20 68 61 | don't.always ha|
000000b0 76 65 20 74 68 65 20 66 75 6c 6c 20 63 6f 6d 70 |ve the full comp|
000000c0 6c 65 6d 65 6e 74 20 6f 66 20 6e 65 69 67 68 62 |lement of neighb|
000000d0 6f 75 72 73 2e 0a 20 20 41 72 63 41 75 74 20 61 |ours.. ArcAut a|
000000e0 6c 6c 6f 77 73 20 74 77 6f 20 73 6f 6c 75 74 69 |llows two soluti|
000000f0 6f 6e 73 2e 20 57 65 20 63 61 6e 20 65 69 74 68 |ons. We can eith|
00000100 65 72 20 69 64 65 6e 74 69 66 79 20 74 68 65 20 |er identify the |
00000110 6c 65 66 74 20 68 61 6e 64 20 65 64 67 65 20 77 |left hand edge w|
00000120 69 74 68 20 74 68 65 20 72 69 67 68 74 20 68 61 |ith the right ha|
00000130 6e 64 20 65 64 67 65 2c 20 61 73 20 69 66 20 74 |nd edge, as if t|
00000140 68 65 79 20 77 65 72 65 20 73 69 64 65 20 62 79 |hey were side by|
00000150 20 73 69 64 65 2c 0a 26 20 73 69 6d 69 6c 61 72 | side,.& similar|
00000160 6c 79 2c 20 74 68 65 20 74 6f 70 20 77 69 74 68 |ly, the top with|
00000170 20 74 68 65 20 62 6f 74 74 6f 6d 2e 20 54 68 65 | the bottom. The|
00000180 20 72 65 73 75 6c 74 20 69 73 20 74 68 61 74 20 | result is that |
00000190 77 65 20 6e 6f 20 6c 6f 6e 67 65 72 20 68 61 76 |we no longer hav|
000001a0 65 20 61 6e 79 20 65 64 67 65 73 20 74 6f 20 77 |e any edges to w|
000001b0 6f 72 72 79 20 61 62 6f 75 74 21 20 54 68 65 20 |orry about! The |
000001c0 77 69 6e 64 6f 77 20 65 66 66 65 63 74 69 76 65 |window effective|
000001d0 6c 79 0a 63 6f 72 72 65 73 70 6f 6e 64 73 20 74 |ly.corresponds t|
000001e0 6f 20 74 68 65 20 73 75 72 66 61 63 65 20 6f 66 |o the surface of|
000001f0 20 61 20 74 6f 72 75 73 20 6f 72 20 64 6f 75 67 | a torus or doug|
00000200 68 6e 75 74 20 28 74 68 65 20 73 6f 72 74 20 77 |hnut (the sort w|
00000210 69 74 68 20 61 20 68 6f 6c 65 20 69 6e 20 74 68 |ith a hole in th|
00000220 65 20 6d 69 64 64 6c 65 29 2e 20 54 68 65 20 6f |e middle). The o|
00000230 74 68 65 72 20 70 6f 73 73 69 62 69 6c 69 74 79 |ther possibility|
00000240 20 69 73 20 74 6f 20 6c 65 74 20 74 68 65 0a 61 | is to let the.a|
00000250 75 74 6f 6d 61 74 6f 6e 20 62 65 68 61 76 65 20 |utomaton behave |
00000260 61 73 20 69 66 20 74 68 65 20 62 6f 72 64 65 72 |as if the border|
00000270 20 6f 66 20 63 65 6c 6c 73 20 73 75 72 72 6f 75 | of cells surrou|
00000280 6e 64 69 6e 67 20 74 68 65 20 77 69 6e 64 6f 77 |nding the window|
00000290 20 64 6f 20 65 78 69 73 74 2c 20 62 75 74 20 61 | do exist, but a|
000002a0 72 65 20 66 6f 72 63 65 64 20 74 6f 20 6d 61 69 |re forced to mai|
000002b0 6e 74 61 69 6e 20 61 20 66 69 78 65 64 20 73 74 |ntain a fixed st|
000002c0 61 74 65 2e 20 54 68 69 73 20 69 73 0a 75 73 65 |ate. This is.use|
000002d0 64 20 69 6e 20 74 68 65 20 63 75 72 72 65 6e 74 |d in the current|
000002e0 20 64 65 66 69 6e 69 74 69 6f 6e 20 6f 66 20 27 | definition of '|
000002f0 4c 69 66 65 27 2e 20 49 74 20 69 73 20 61 20 75 |Life'. It is a u|
00000300 73 65 66 75 6c 20 66 61 63 69 6c 69 74 79 20 69 |seful facility i|
00000310 66 20 77 65 20 77 61 6e 74 20 74 6f 20 70 72 65 |f we want to pre|
00000320 76 65 6e 74 20 27 6f 62 6a 65 63 74 73 27 20 73 |vent 'objects' s|
00000330 75 63 68 20 61 73 20 67 6c 69 64 65 72 73 2c 20 |uch as gliders, |
00000340 77 61 6e 64 65 72 69 6e 67 20 6f 66 66 20 6f 6e |wandering off on|
00000350 65 20 73 69 64 65 20 6f 66 20 74 68 65 20 77 69 |e side of the wi|
00000360 6e 64 6f 77 2c 20 6f 6e 6c 79 20 74 6f 20 72 65 |ndow, only to re|
00000370 61 70 70 65 61 72 20 6f 6e 20 74 68 65 20 6f 74 |appear on the ot|
00000380 68 65 72 2c 20 26 20 74 68 65 6e 20 67 6f 20 26 |her, & then go &|
00000390 20 69 6e 74 65 72 66 65 72 65 20 77 69 74 68 20 | interfere with |
000003a0 77 68 61 74 65 76 65 72 20 69 73 20 68 61 70 70 |whatever is happ|
000003b0 65 6e 69 6e 67 20 69 6e 20 74 68 65 20 63 65 6e |ening in the cen|
000003c0 74 72 65 2e 0a 0a 0a 20 20 4e 61 6d 65 20 6f 66 |tre.... Name of|
000003d0 20 73 79 73 74 65 6d 20 76 61 72 69 61 62 6c 65 | system variable|
000003e0 20 20 20 20 20 20 50 6f 73 73 69 62 6c 65 20 76 | Possible v|
000003f0 61 6c 75 65 73 20 20 20 20 20 20 20 44 65 66 61 |alues Defa|
00000400 75 6c 74 20 76 61 6c 75 65 20 20 20 20 20 20 20 |ult value |
00000410 20 20 4d 65 61 6e 69 6e 67 0a 0a 20 20 20 20 20 | Meaning.. |
00000420 20 20 20 20 20 77 72 61 70 20 20 20 20 20 20 20 | wrap |
00000430 20 20 20 20 20 20 20 20 20 20 6f 6e 7c 6f 66 66 | on|off|
00000440 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 | |
00000450 6f 6e 20 20 20 20 20 20 20 20 20 20 20 20 20 20 |on |
00000460 20 20 20 20 20 20 73 65 6c 65 63 74 73 20 77 68 | selects wh|
00000470 65 74 68 65 72 20 74 68 65 20 43 41 20 75 6e 69 |ether the CA uni|
00000480 76 65 72 73 65 20 68 61 73 20 77 72 61 70 2d 61 |verse has wrap-a|
00000490 72 6f 75 6e 64 20 6f 72 0a 20 20 20 20 20 20 20 |round or. |
000004a0 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 | |
*
000004e0 20 20 20 20 69 73 20 62 6f 72 64 65 72 65 64 20 | is bordered |
000004f0 62 79 20 63 65 6c 6c 73 20 6f 66 20 61 20 66 69 |by cells of a fi|
00000500 78 65 64 20 73 74 61 74 65 0a 20 20 20 20 20 20 |xed state. |
00000510 20 20 62 6f 72 64 65 72 20 20 20 20 20 20 20 20 | border |
00000520 20 20 20 20 20 20 20 20 20 7b 30 2c 31 2c 2e 20 | {0,1,. |
00000530 2e 20 2e 2c 32 35 35 7d 20 20 20 20 20 20 20 6e |. .,255} n|
00000540 6f 20 64 65 66 61 75 6c 74 20 20 20 20 20 20 20 |o default |
00000550 20 20 20 20 20 73 70 65 63 69 66 69 65 73 20 63 | specifies c|
00000560 65 6c 6c 20 73 74 61 74 65 20 66 6f 72 20 62 6f |ell state for bo|
00000570 72 64 65 72 3b 20 75 73 65 64 20 77 68 65 6e 20 |rder; used when |
00000580 77 72 61 70 3d 6f 66 66 0a 20 20 20 20 20 20 20 |wrap=off. |
00000590 20 20 20 6e 65 69 67 20 20 20 20 20 20 20 20 20 | neig |
000005a0 20 20 20 20 20 20 20 20 6d 6f 6f 72 65 7c 6d 61 | moore|ma|
000005b0 72 67 6f 6c 75 73 20 20 20 20 20 20 20 20 6d 6f |rgolus mo|
000005c0 6f 72 65 20 20 20 20 20 20 20 20 20 20 20 20 20 |ore |
000005d0 20 20 20 20 73 65 6c 65 63 74 73 20 74 68 65 20 | selects the |
000005e0 74 79 70 65 20 6f 66 20 6e 65 69 67 68 62 6f 75 |type of neighbou|
000005f0 72 68 6f 6f 64 20 72 65 71 75 69 72 65 64 20 62 |rhood required b|
00000600 79 20 74 68 65 0a 20 20 20 20 20 20 20 20 20 20 |y the. |
00000610 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 | |
*
00000650 20 61 75 74 6f 6d 61 74 6f 6e 3b 20 73 65 65 20 | automaton; see |
00000660 74 61 62 6c 65 20 33 0a 20 20 20 20 20 20 20 20 |table 3. |
00000670 20 20 66 6c 61 67 20 20 20 20 20 20 20 20 20 20 | flag |
00000680 20 20 20 20 20 20 20 30 7c 33 7c 34 7c 37 20 20 | 0|3|4|7 |
00000690 20 20 20 20 20 20 20 20 20 20 20 20 20 30 20 20 | 0 |
000006a0 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 | |
000006b0 20 20 20 75 73 65 64 20 77 68 65 6e 20 6e 65 69 | used when nei|
000006c0 67 3d 6d 61 72 67 6f 6c 75 73 3b 20 73 70 65 63 |g=margolus; spec|
000006d0 69 66 69 65 73 20 77 68 65 74 68 65 72 20 61 75 |ifies whether au|
000006e0 74 6f 6d 61 74 6f 6e 0a 20 20 20 20 20 20 20 20 |tomaton. |
000006f0 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 | |
*
00000730 20 20 20 63 6f 64 65 20 72 65 67 69 73 74 65 72 | code register|
00000740 20 46 4c 41 47 20 73 68 6f 75 6c 64 20 72 65 74 | FLAG should ret|
00000750 75 72 6e 3a 0a 20 20 20 20 20 20 20 20 20 20 20 |urn:. |
00000760 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 | |
*
00000790 20 20 20 20 20 20 20 20 30 20 20 20 20 20 20 20 | 0 |
000007a0 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 | |
*
000007c0 20 20 20 20 20 20 20 20 20 20 20 3b 69 66 20 66 | ;if f|
000007d0 6c 61 67 3d 30 0a 20 20 20 20 20 20 20 20 20 20 |lag=0. |
000007e0 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 | |
*
00000810 20 20 20 20 20 20 20 20 20 30 7c 31 7c 32 7c 33 | 0|1|2|3|
00000820 20 64 65 70 65 6e 64 69 6e 67 20 6f 6e 20 43 45 | depending on CE|
00000830 4c 4c 27 73 20 70 6f 73 69 74 69 6f 6e 20 77 69 |LL's position wi|
00000840 74 68 69 6e 20 62 6c 6f 63 6b 0a 20 20 20 20 20 |thin block. |
00000850 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 | |
*
00000890 20 20 20 20 20 20 30 20 66 6f 72 20 55 4c 2c 20 | 0 for UL, |
000008a0 31 20 66 6f 72 20 55 52 2c 20 32 20 66 6f 72 20 |1 for UR, 2 for |
000008b0 4c 4c 2c 20 33 20 66 6f 72 20 4c 52 20 20 20 20 |LL, 3 for LR |
000008c0 20 3b 69 66 20 66 6c 61 67 3d 33 0a 20 20 20 20 | ;if flag=3. |
000008d0 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 | |
*
00000900 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 30 | 0|
00000910 7c 34 20 20 20 20 20 64 65 70 65 6e 64 69 6e 67 ||4 depending|
00000920 20 6f 6e 20 74 68 65 20 70 68 61 73 65 0a 20 20 | on the phase. |
00000930 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 | |
*
00000970 20 20 20 20 20 20 20 20 20 30 20 66 6f 72 20 65 | 0 for e|
00000980 76 65 6e 20 70 68 61 73 65 2c 20 34 20 66 6f 72 |ven phase, 4 for|
00000990 20 6f 64 64 20 70 68 61 73 65 20 20 20 20 20 20 | odd phase |
000009a0 20 20 20 20 3b 69 66 20 66 6c 61 67 3d 34 0a 20 | ;if flag=4. |
000009b0 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 | |
*
000009f0 20 20 30 20 74 6f 20 37 20 20 74 68 65 20 73 75 | 0 to 7 the su|
00000a00 6d 20 6f 66 20 74 68 65 20 61 62 6f 76 65 20 74 |m of the above t|
00000a10 77 6f 20 69 74 65 6d 73 20 20 20 20 20 20 20 20 |wo items |
00000a20 20 20 20 20 20 3b 69 66 20 66 6c 61 67 3d 37 0a | ;if flag=7.|
00000a30 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 | |
*
00000a70 20 20 20 20 20 20 20 20 20 20 20 73 65 65 20 74 | see t|
00000a80 61 62 6c 65 20 33 0a 20 20 20 20 20 20 20 20 20 |able 3. |
00000a90 20 72 6e 64 62 20 20 20 20 20 20 20 20 20 20 20 | rndb |
00000aa0 20 20 20 20 20 20 6f 6e 7c 6f 66 66 20 20 20 20 | on|off |
00000ab0 20 20 20 20 20 20 20 20 20 20 20 20 6f 66 66 20 | off |
00000ac0 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 | |
00000ad0 20 20 77 68 65 6e 20 6e 65 69 67 3d 6d 61 72 67 | when neig=marg|
00000ae0 6f 6c 75 73 20 26 20 61 75 74 6f 6d 61 74 6f 6e |olus & automaton|
00000af0 20 72 65 71 75 69 72 65 73 20 75 73 65 20 6f 66 | requires use of|
00000b00 20 74 68 65 0a 20 20 20 20 20 20 20 20 20 20 20 | the. |
00000b10 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 | |
*
00000b50 52 4e 44 42 20 63 6f 6d 6d 61 6e 64 2c 20 79 6f |RNDB command, yo|
00000b60 75 20 6d 75 73 74 20 73 65 74 20 72 6e 64 62 20 |u must set rndb |
00000b70 74 6f 20 6f 6e 3b 0a 20 20 20 20 20 20 20 20 20 |to on;. |
00000b80 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 | |
*
00000bc0 20 20 73 65 65 20 74 61 62 6c 65 73 20 32 20 26 | see tables 2 &|
00000bd0 20 33 20 61 6e 64 20 65 78 61 6d 70 6c 65 20 44 | 3 and example D|
00000be0 4c 41 20 61 75 74 6f 6d 61 74 6f 6e 0a 0a 20 20 |LA automaton.. |
00000bf0 54 6f 20 73 65 74 20 61 6e 79 20 6f 66 20 74 68 |To set any of th|
00000c00 65 73 65 20 76 61 6c 75 65 73 20 69 6e 63 6c 75 |ese values inclu|
00000c10 64 65 20 61 20 63 6f 6d 6d 61 6e 64 2c 20 66 6f |de a command, fo|
00000c20 72 20 65 78 61 6d 70 6c 65 20 27 2a 53 65 74 45 |r example '*SetE|
00000c30 76 61 6c 20 77 72 61 70 20 6f 66 66 27 2c 20 77 |val wrap off', w|
00000c40 69 74 68 69 6e 20 74 68 65 20 62 6f 64 79 20 6f |ithin the body o|
00000c50 66 20 74 68 65 20 70 72 6f 63 65 64 75 72 65 20 |f the procedure |
00000c60 63 61 6c 6c 65 64 20 64 6f 2c 20 69 6e 0a 74 68 |called do, in.th|
00000c70 65 20 73 65 63 74 69 6f 6e 20 6f 66 20 74 65 78 |e section of tex|
00000c80 74 20 62 65 74 77 65 65 6e 20 49 4e 49 54 49 41 |t between INITIA|
00000c90 4c 49 53 41 54 49 4f 4e 2a 20 26 20 53 43 52 45 |LISATION* & SCRE|
00000ca0 45 4e 2a 20 3b 20 73 65 65 20 73 6f 6d 65 20 6f |EN* ; see some o|
00000cb0 66 20 74 68 65 20 61 75 74 6f 6d 61 74 6f 6e 73 |f the automatons|
00000cc0 20 70 72 6f 76 69 64 65 64 20 66 6f 72 20 65 78 | provided for ex|
00000cd0 61 6d 70 6c 65 73 2e 0a 20 20 59 6f 75 20 6d 61 |amples.. You ma|
00000ce0 79 20 61 6c 73 6f 20 75 73 65 20 74 68 69 73 20 |y also use this |
00000cf0 70 72 6f 63 65 64 75 72 65 20 74 6f 20 61 6c 6c |procedure to all|
00000d00 6f 77 20 74 68 65 20 75 73 65 72 20 74 6f 20 69 |ow the user to i|
00000d10 6e 70 75 74 20 70 61 72 61 6d 65 74 65 72 73 20 |nput parameters |
00000d20 6e 65 65 64 65 64 20 62 79 20 79 6f 75 72 20 61 |needed by your a|
00000d30 75 74 6f 6d 61 74 6f 6e 3b 20 6e 6f 74 65 2c 20 |utomaton; note, |
00000d40 74 68 65 73 65 20 6d 75 73 74 20 61 6c 73 6f 20 |these must also |
00000d50 62 65 20 70 61 73 73 65 64 20 74 6f 20 74 68 65 |be passed to the|
00000d60 20 72 65 73 74 20 6f 66 20 74 68 65 20 61 75 74 | rest of the aut|
00000d70 6f 6d 61 74 6f 6e 20 76 69 61 20 73 79 73 74 65 |omaton via syste|
00000d80 6d 20 76 61 72 69 61 62 6c 65 73 2e 20 53 65 65 |m variables. See|
00000d90 20 66 6f 72 20 65 78 61 6d 70 6c 65 20 74 68 65 | for example the|
00000da0 20 61 75 74 6f 6d 61 74 6f 6e 73 20 44 65 6d 6f | automatons Demo|
00000db0 6e 20 26 20 46 72 61 63 47 72 6f 77 2e |n & FracGrow.|
00000dbd 
.