Direct approximation: Difference between revisions

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Trying to make sure the text reads well, though I don't know if I'm succeeding at this or not.
Aura (talk | contribs)
Something tells me that the information regarding patent vals needs to be above the list of examples- if this is wrong, let me know.
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  round(log2(r)*nEdo)
  round(log2(r)*nEdo)
A [[patent val]] is the best mapping of a representative set of intervals (taken to be [[generator]]s for a [[JI subgroup]]) in a given EDO; for the ''p''-[[prime limit]] this set consists of [[prime interval]]s.  Just as the patent val itself can be referred to as the "nearest edomapping", so a patent interval can be referred to as a "direct mapping".


; Some Examples
; Some Examples
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A [[patent val]] is the best mapping of a representative set of intervals (taken to be [[generator]]s for a [[JI subgroup]]) in a given EDO; for the ''p''-[[prime limit]] this set consists of [[prime interval]]s.  Just as the patent val itself can be referred to as the "nearest edomapping", so a patent interval can be referred to as a "direct mapping".


[[Category:Terms]]
[[Category:Terms]]
[[Category:Method]]
[[Category:Method]]
[[Category:Val]]
[[Category:Val]]

Revision as of 16:50, 19 January 2021

A patent interval in a given EDO is the number of EDO steps needed to reach the best approximation of a given interval – usually, but not necessarily just – in that EDO. The method for calculating patent intervals is referred to as direct mapping, and it involves rounding the product of the binary logarithm (log2) of the interval ratio (r) and the EDO number (nEdo).

round(log2(r)*nEdo)

A patent val is the best mapping of a representative set of intervals (taken to be generators for a JI subgroup) in a given EDO; for the p-prime limit this set consists of prime intervals. Just as the patent val itself can be referred to as the "nearest edomapping", so a patent interval can be referred to as a "direct mapping".

Some Examples
\ 12edo 17edo 19edo 26edo
3/2 7 10 11 15
5/4 4 5 6 8
6/5 3 4 5 7
7/4 10 14 15 21