Implementing a Rule

Mon, 01 Jan 0001 00:00:00 +0000

The transition function

In JCAL, the transition function (σ) is the core of any cellular automaton. It determines how each cell evolves from one generation to the next.

To define a transition function, extend CellularAutomataExecutor and implement the singleRun method. JCAL calls this method once per cell per generation, passing the current cell and its neighbors. Return a new DefaultCell carrying the cell’s next state.

singleRun(cell, neighbors) → next cell state

Example: Conway’s Game of Life executor

public class GOLExecutor extends CellularAutomataExecutor {

	@Override
	public DefaultCell singleRun(DefaultCell cell, List<DefaultCell> neighbors) {
		
       	DefaultStatus dead = new DefaultStatus("dead", "0");
       	DefaultStatus alive = new DefaultStatus("alive", "1");
		Long alives = neighbors.stream().filter(item -> item.currentStatus.equals(alive)).count();	
		DefaultCell toReturn = new DefaultCell(null, cell.getRow(), cell.getCol());	
		if (cell.currentStatus.equals(dead) && alives == 3) {
			toReturn.currentStatus = alive;
		} else if (cell.currentStatus.equals(alive) && (alives == 2 || alives == 3)) {
			toReturn.currentStatus = alive;
		} else {
			toReturn.currentStatus = dead;
		}
		return toReturn;
	}
}

Running the cellular automaton

Once you have an executor, wire it together with a configured grid and call run:

Implementing a Rule on JCAL Docs

Implementing a Rule

The transition function

Example: Conway’s Game of Life executor

Running the cellular automaton