[Back to main page]

Oscillizer glossary

It is assumed that you are already familiar with the terminology commonly used in Conway's Game of Life. The purpose of this glossary is to define exactly what Oscillizer is measuring. The terms are not guaranteed to mean exactly the same thing in other contexts, and not all are in common use.

active cells
The set of those cells that are ON in at least one phase; the union of the rotor and stator.
bounding box
The smallest orthogonally-oriented rectangle that contains all of the active cells. For bounding box purposes, cells are considered to be squares that tile the plane, not points. For example, the bounding box of a blinker is 3x3, not 2x2 (or 3x1).
cell period
The minimum number of generations it takes for the ON/OFF pattern of an individual cell (belonging to an oscillator) to repeat. This must necessarily be a factor of the period of the oscillator.
heat
The average number of cells that change state per generation. Oscillizer also calculates the "minimum heat" (and "maximum heat"), which is the minimum (maximum) number of cells that change state in one generation. See also temperature.
mixed period
An oscillator has a "mixed" period if its highest cell period is less than its full period. For example, a pattern consisting of a noninteracting period 4 oscillator and period 6 oscillator would technically have a period of 12, but no single cell would have a period higher than 6.
oscillator
A finite nonempty pattern that recurs at the same position and orientation after some fixed number of generations. A still life is considered to be an oscillator whose period is 1.
period
The minimum number of generations it takes for an oscillator to recur at the same position and orientation. See also cell period and mixed period.
rotor
The set of those cells that are ON in at least one phase and also OFF in at least one other phase.
rotor temperature
The average percentage of rotor cells that change state per generation. This is undefined for still lifes, which have no rotor.
rule
The cellular automata rules in which this oscillator works. The minimum rule is listed first, then the maximum rule (if the oscillator works in more than one rule). Optional Birth and Survival counts are underlined in the web-based version of Oscillizer. [Note: Only rules in which the oscillator works in exactly the same way as the given rule are listed. The pattern may well be a different oscillator in some other rule, but that rule will not be shown.]
stator
The set of those cells that are ON in all phases.
temperature
The average percentage of active cells that change state per generation. See also rotor temperature, heat.
size
"Size" usually means the number of cells.
volatility
The percentage of active cells which belong to the rotor.
strict volatility
The percentage of active cells which oscillate at the full period of the oscillator (rather than some factor of that period). Note that for prime periods, strict volatility must equal volatility.