A simple cellular automaton in Python
How do rules work?
A rule determines how cells evolve over time. Rules are expressed as integers ranging between 0 - 255 (8 bits). The evolution of the cells is easier to understand by looking at the binary representation.
Example:
Let's look at rule 30. In binary this is:
30 = 0b00011110
Now each bit corresonds to a state for three adjacent cells and the value of that bit corresponds to what the next state in the evolution of the center cell is.
Bit 7 6 5 4 3 2 1 0
Previous: 111 110 101 100 011 010 001 000
Rule 30 : [0] [0] [0] [1] [1] [1] [1] [0]
So according to rule 30, 4 possible combinations of cells lead to a 1 in the center cell.
Here's what a single 1 in the centre evolves to over time with rule 30. I've represented 1's with '-' and 0's as ' '
-
---
-- -
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