Pattern naming: Difference between revisions

Revision as of 10:51, 20 June 2016

Patterns in Conway's Game of Life and related cellular automata may be named in a variety of ways.

There are three ways to refer to a pattern:

A name designates the pattern.
A descriptions provides information about the pattern and its parameters.
A code allows reconstruction of the pattern.

Proper names

Many patterns have proper names assigned to them, either by their discoverer of the Life community at large. Names are usually based on either the visual appearance of the pattern, its behavior, or its parameters; examples include:

Patterns named after their visual appearance: block, copperhead (resembling the head of a copperhead snake).
Patterns named after their behavior: glider, boat maker.
Patterns named after their parameters: pentadecathlon (period 15 oscillator).

Infinite families

Main article: Long

Many patterns can be extended arbitrarily in a systematic manner; the members of the family are then referred to as long, very long, extra long etc.

Other infinite families defying easy description exist, e.g. lakes; these are largely unnamed.

Systematic names (descriptions)

Patterns may be given systematic names based on their behavior and/or traits.

Shuttles, loops and oscillators may be named according to their period; for example, the p26 glider shuttle, p42 glider shuttle and p50 glider shuttle are all glider shuttles of various periods.

Sawtooths are often named according to their minimum recurring population, e.g. sawtooth 177, sawtooth 201 and sawtooth 1212.

Unnamed patterns

Entirely unnamed patterns are referred to using a descriptor.

For oscillators, the format of the descripter is #p#. The first number denotes the smallest amount of cells in any generation; the second denotes the period. For spaceships, this is extended to #p#h#v#. The third and fourth the horizontal and vertical displacement of the ship, relative to its initial position.

In either case, objects that would ordinarily be assigned the same descriptor may be distinguished by appending a period and an index, e.g. 28P7.1 and 28P7.2.

Codes

Also see Category:File formats.

Various encodings for patterns exist.

RLE is easy to encode and decode, but can grow fairly large, and does not uniquely identify a pattern.
Extended Wechsler codes (apgcodes) uniquely identify a pattern, while also encoding its behavior in a given rule (assumed to be Conway Life unless otherwise specified).

Indices in pattern collections

Unnammed patterns can also be described by their indices in pattern collections; for example, the hat is object 9.1 on Pentadecathlon.com. For stamp collections such as jslife, the file the object is contained in and its position on the grid can be used.

@@ Line 1: / Line 1: @@
-{{stub}}
+Patterns in [[Conway's Game of Life]] and [[Life-like cellular automaton|related cellular automata]] may be '''named''' in a variety of ways.
-'''Unnamed patterns''' are referred to using a descriptor.
+There are three ways to refer to a pattern:
+* A ''name'' designates the pattern.
+* A ''descriptions'' provides information about the pattern and its parameters.
+* A ''code'' allows reconstruction of the pattern.
+==Proper names==
+Many patterns have proper names assigned to them, either by their discoverer of the [[Life enthusiast|Life community]] at large. Names are usually based on either the visual appearance of the pattern, its behavior, or its parameters; examples include:
+* Patterns named after their visual appearance: [[block]], [[copperhead]] (resembling the head of a copperhead snake).
+* Patterns named after their behavior: [[glider]], [[boat maker]].
+* Patterns named after their parameters: [[pentadecathlon]] ([[:Category:Oscillators with period 15|period 15]] [[oscillator]]).
+===Infinite families===
+{{Main|Long}}
+Many patterns can be extended arbitrarily in a systematic manner; the members of the family are then referred to as [[long]], very long, extra long etc.
+Other infinite families defying easy description exist, e.g. [[lake]]s; these are largely unnamed.
+==Systematic names (descriptions) ==
+Patterns may be given systematic names based on their behavior and/or traits.
+Shuttles, loops and oscillators may be named according to their period; for example, the [[p26 glider shuttle]], [[p42 glider shuttle]] and [[p50 glider shuttle]] are all glider shuttles of various [[period]]s.
+[[Sawtooth]]s are often named according to their minimum recurring population, e.g. [[sawtooth 177]], [[sawtooth 201]] and [[sawtooth 1212]].
+===Unnamed patterns===
+Entirely unnamed patterns are referred to using a descriptor.
 For oscillators, the format of the descripter is <tt>#p#</tt>. The first number denotes the smallest amount of cells in any generation; the second denotes the [[period]]. For spaceships, this is extended to <tt>#p#h#v#</tt>. The third and fourth the horizontal and vertical displacement of the ship, relative to its initial position.
@@ Line 6: / Line 34: @@
 In either case, objects that would ordinarily be assigned the same descriptor may be distinguished by appending a period and an index, e.g. [[28P7.1]] and [[28P7.2]].
-== Also see ==
+==Codes==
-* [[Apgsearch format]]
+:''Also see [[:Category:File formats]].''
+Various encodings for patterns exist.
+* [[RLE]] is easy to encode and decode, but can grow fairly large, and does not uniquely identify a pattern.
+* [[Apgsearch format|Extended Wechsler code]]s (apgcodes) uniquely identify a pattern, while also encoding its behavior in a given rule (assumed to be [[Conway's Game of Life|Conway Life]] unless otherwise specified).
+==Indices in pattern collections==
+Unnammed patterns can also be described by their indices in pattern collections; for example, the [[hat]] is [http://www.pentadecathlon.com/objects/object-info.php?objid=9.1 object 9.1] on [[Pentadecathlon.com]]. For stamp collections such as [[jslife]], the file the object is contained in and its position on the grid can be used.
+__NOTOC__