More than one dimension

There are interesting coincidences of neighborhood size between one dimensional automata and various multidimensional automata; mostly such coincidences occur for automata of fairly large radii. Those combinations for which dual, treble, or higher dimensionality is appropriate have their own lists of operators, most all of which are to be found in the probability submenu.

The LCAU KR programs with K=2 and R in the range from 3 to 6 are primarily designed to explore automata of the kind described in the article of Chaté and Manneville, previously cited.

These automata are multidimensional, so each LCAU within the relevant range has been modified to include several multidimensional neighborhoods having the same volume as the corresponding one dimensional automaton. Also, for better statistics, an array with 16K cells has been included, even though this interferes with the de Bruijn option d and with editing the cell array l.

The only effective submenu for this subset of LCAU programs is t, the probability option. However, the main menu is still required to define the rule; to do that is so cumbersome that only totalistic T or semitotalistic S definitions are practical. Random lines y and random rules x can still be generated, and the evolution can still be viewed line by line g. The ancestor option e was never implemented for these automata.

Exit from almost everything, especially the submenus, is via CARRIAGE RETURN. To avoid inadvertently abandoning the main program, its own termination lies with q, as always.

The function key f1 will produce a list of demonstrations, which is essentially nonexistent in these programs. However, f2 will produce a list of REC demonstrations from which a selection can be made by moving the cursor. These, although not numerous, are designed to show off the Chaté-Manneville automata, otherwise describable as ``electronic Swiss cheeses.''

The REC program for the selected demonstration may be displayed and edited using the key f3. Within the f3 option, keys f1 and f2 will display panels giving a concise summary of REC and its syntax, but this should have been learned separately by having previously read the appropriate documentation files. Page-up and Page-down will scroll through all the valid REC symbols; likewise moving the editor's cursor with arrows or an external mouse (which has been programmed to transmit the arrows) will gloss the designated symbol.

REC programs are to be edited from the main menu, but executed from the probability submenu; this is purely a consequence of changing between the screen modes which are most convenient for the two activities. A similar remark applies to the way that the rule number gets defined.

Harold V. McIntosh