Ploidacot: Difference between revisions

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* [[tricot]] is alpha-tricot
* [[tricot]] is alpha-tricot
* [[porcupine]] is beta-tricot
* [[porcupine]] is beta-tricot
* [[hedgehog]] is diploid delta-tricot
* [[hedgehog]] is diploid alpha-tricot
* [[tetracot]] is tetracot
* [[tetracot]] is tetracot
* [[squares]] is beta-tetracot
* [[squares]] is beta-tetracot

Revision as of 08:32, 12 April 2022

The Ploidacot system is a classification of rank 2 temperaments based on pergen, i.e. how a temperament can be thought of as a union of copies of Pythagorean tuning.

Ploidacot is a canonical naming system for pergen squares in that every pergen square that covers both 2/1 and 3/2 has a unique name in the Ploidacot system.

Ploids

Any rank 2 temperament must split the octave into a number of ploids, for instance pajara divides the octave into two so it's diploid. Temperaments that don't divide the octave are called haploid.

Cots

If 3/2 is represented by a linearly independent element to the ploid, there is a number of ploids which when added to 3/2 gives the interval which splits into the largest number of parts by the temperament. Each of these parts is called a cot or cotyledon and the Ploidacot system uses a Greek letter to describe the smallest number of ploids should be added to 3/2 to form a whole number of cots, and this number of cots is indicated by a Greek numerical prefix.

Examples

Notation

Todo: come up with canonical ups and downs notation systems for pergen squares