Pulse divider
A pulse divider is a conduit that lets every n-th input signal pass through, for some positive integer n > 1; one output signal is produced for every n received input signals. The signals are typically gliders, spaceships or Herschels.
Common examples of pulse dividers include the semi-Snarks, higher-factor variants such as the tremi-Snark, and a number of period-multiplying Herschel conduits.
Composing pulse dividers causes their factors to multiply; a sexti-Snark could be built from the composition of a semi-Snark and a tremi-Snark. A popular application of chains of pulse dividers is to make a binary counter.
Pulse dividers should be distinguished from period multipliers. While a pulse divider can be used as a period multiplier for streams of sufficiently high periods, pulse dividers are more general, in that there is no requirement that the input signals be uniformly spaced. For that reason, pulse dividers have been used to construct large-prime-period guns; this is beyond the scope of period-multiplying.
A pulse divider may be stable (composed of still lifes) or periodic (containing oscillators). An example of a periodic (p5) pulse divider is the p5 quinti-Snark; it contains a p5 oscillator, leading to a modulo-5 restriction on the timing of every fifth glider, but otherwise the input stream is not restricted.
External links
- Pulse divider at the Life Lexicon
- I'm looking for period multiplicating Herschel Tracks. (discussion thread) at the ConwayLife.com forums
- "pulse divider". ConwayLife.com.