Octohash database: Difference between revisions

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Several databases implemented using the octohash function can be used to search for active reactions that produce a given pattern (which may be active or settled). The databases are designed to work with [[Golly]] and [[Python]], without other dependencies.
Several databases implemented using the octohash function can be used to search for active reactions that produce a given pattern (which may be active or settled). The databases are designed to work with [[Golly]] and [[Python]], without other dependencies.


The ''octohash database''<ref name="db_octohash" /> catalogues every generation of every possible collision between a single [[glider]] and all possible [[constellation]]s of up to two well-separated objects (excluding [[pseudo still life]]s) fitting inside a {{times|12|12}} bounding box; the included objects are [[block]], [[tub]], [[boat]], [[beehive]], [[ship]], [[loaf]], [[eater]], [[pond]], [[long boat]], and [[blinker]].
The ''octohash database''<ref name="db_octohash" /><ref name="thread4660" />, published in August 2020, catalogues every generation of every possible collision between a single [[glider]] and all possible [[constellation]]s of up to two well-separated objects (excluding [[pseudo still life]]s) fitting inside a {{times|12|12}} bounding box; the included objects are [[block]], [[tub]], [[boat]], [[beehive]], [[ship]], [[loaf]], [[eater]], [[pond]], [[long boat]], and [[blinker]].


The ''octo3obj database''<ref name="db_octo3obj" /> catalogues every generation of every possible collision between a single glider and all possible constellations of up to three well-separated patterns fitting inside an {{times|11|11}} bounding box; the included objects and constellations are [[blinker]], [[block]], [[beehive]], [[bi-block]], [[half blockade]], and [[teardrop]] ash (two beehives).
The ''octo3obj database''<ref name="db_octo3obj" /><ref name="post147380" />, finished in June 2022, catalogues every generation of every possible collision between a single glider and all possible constellations of up to three well-separated patterns fitting inside an {{times|11|11}} bounding box; the included objects and constellations are [[blinker]], [[block]], [[beehive]], [[bi-block]], [[half blockade]], and [[teardrop]] ash (two beehives).


The ''octo3g database''<ref name="post149677" /><ref name="db_octo3g" /> catalogues every generation of a subset of [[three-glider collision]]s.
The ''octo3g database''<ref name="db_octo3g" /><ref name="post149677" /><ref name="post150819" />, completed in August 2022, catalogues every generation of every collision in a subset of [[three-glider collision]]s, making it possible to search active 3G collision patterns in the same way as active patterns in the previous octo3obj and octohash databases.


==See also==
==See also==
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<ref name="db_octo3obj">[https://github.com/dvgrn/octo3obj {{filename|dvgrn/octo3obj}}] on GitHub</ref>
<ref name="db_octo3obj">[https://github.com/dvgrn/octo3obj {{filename|dvgrn/octo3obj}}] on GitHub</ref>
<ref name="db_octo3g">[https://github.com/dvgrn/octo3g {{filename|dvgrn/octo3g}}] on GitHub</ref>
<ref name="db_octo3g">[https://github.com/dvgrn/octo3g {{filename|dvgrn/octo3g}}] on GitHub</ref>
<ref name="thread4660">{{LinkForumThread
|format  = ref
|t      = 4660
|title  = Octohash fingerprints
}}</ref>
<ref name="post147380">{{LinkForumThread
|format  = ref
|p      = 147380
|title  = Re: Octohash fingerprints
|author  = Dave Greene
|date    = June 21, 2022
}}</ref>


<ref name="post149677">{{LinkForumThread
<ref name="post149677">{{LinkForumThread
Line 27: Line 41:
|author  = Dave Greene
|author  = Dave Greene
|date    = August 17, 2022
|date    = August 17, 2022
}}</ref>
<ref name="post150819">{{LinkForumThread
|format  = ref
|p      = 150819
|title  = Re: NewLifeCA Back Issues
|author  = Dave Greene
|date    = September 10, 2022
}}</ref>
}}</ref>



Revision as of 22:33, 19 October 2022

This article is a stub. You can help LifeWiki by expanding it.

The octohash function is a hash function that returns the same value for any of the eight orientations of a pattern -- in other words, the octohash of any rotation or reflection of a pattern will always be the same as the octohash of the original pattern.

Several databases implemented using the octohash function can be used to search for active reactions that produce a given pattern (which may be active or settled). The databases are designed to work with Golly and Python, without other dependencies.

The octohash database[1][2], published in August 2020, catalogues every generation of every possible collision between a single glider and all possible constellations of up to two well-separated objects (excluding pseudo still lifes) fitting inside a 12 × 12 bounding box; the included objects are block, tub, boat, beehive, ship, loaf, eater, pond, long boat, and blinker.

The octo3obj database[3][4], finished in June 2022, catalogues every generation of every possible collision between a single glider and all possible constellations of up to three well-separated patterns fitting inside an 11 × 11 bounding box; the included objects and constellations are blinker, block, beehive, bi-block, half blockade, and teardrop ash (two beehives).

The octo3g database[5][6][7], completed in August 2022, catalogues every generation of every collision in a subset of three-glider collisions, making it possible to search active 3G collision patterns in the same way as active patterns in the previous octo3obj and octohash databases.

See also

References

  1. ↑ dvgrn/octohash on GitHub
  2. ↑ Octohash fingerprints (discussion thread) at the ConwayLife.com forums
  3. ↑ dvgrn/octo3obj on GitHub
  4. ↑ Dave Greene (June 21, 2022). Re: Octohash fingerprints (discussion thread) at the ConwayLife.com forums
  5. ↑ dvgrn/octo3g on GitHub
  6. ↑ Dave Greene (August 17, 2022). Re: Enumerating Three-Glider Collisions (discussion thread) at the ConwayLife.com forums
  7. ↑ Dave Greene (September 10, 2022). Re: NewLifeCA Back Issues (discussion thread) at the ConwayLife.com forums