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