A totalistic cellular automaton is a cellular automaton in which the rules depend only on the total (or equivalently, the average) of the values of the cells in a neighborhood. These automata were introduced by Wolfram (1983). Like an elementary cellular automaton, the evolution of a one-dimensional radius-one totalistic cellular automaton can completely be described by a table specifying the state a given cell will have in the next generation based on the average value of the three cells consisting of the cell to its left, the value of the cell itself, and the value of the cell to its right.
For a one-dimensional radius-one -color totalistic automaton with integer
and color values 0, 1, ...,
, there are
possible states for the average
of three cells neighboring a given cell, and a total of
-color totalistic cellular automata, each of which can be indexed
with an
-digit
-ary
number, known as a "code." For example, the table giving the evolution
of the 3-color code
is illustrated above. In this diagram, the possible
average values of the three neighboring cells are shown
in the top row of each panel, and the resulting value the central cell takes in the
next generation is shown below in the center.
generations of the illustrated 3-color totalistic cellular
automaton code
are implemented as CellularAutomaton[
r,
3,
1
,
1
,
0
,
n,
All,
All
].
The evolution of a one-dimensional cellular automaton can be illustrated by starting with the initial state (generation zero) in the first row, the first generation on the second row, and so on. For example, the figures above illustrate the first 20 generations of the code 777 3-color totalistic cellular automaton starting with a single gray cell (left figure) and a single black cell (right figure).
The illustrations above show automata numbers 600, 777, 993, 1020, 1074, and 1083 propagated for 25 generations.
The illustrations above show one-dimensional automata that display apparently random features.
The game of life is an outer-totalistic cellular automaton: its update depends on the state of the central cell and the sum of its eight neighbors separately.