311edo: Difference between revisions
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The 41-limit add-73 add-89 add-101 add-109 add-113 123-odd-limit is represented very close to completely consistently, and as aforementioned, the 77-odd-limit subset of that odd-limit is perfectly consistent, to which a variety of odds can be added that keep perfect consistency, but for comprehensiveness and practical use as a temperament approximating the low-to-mid end of the harmonic series, we consider a larger odd-limit than that which seeks to be more complete. | The 41-limit add-73 add-89 add-101 add-109 add-113 123-odd-limit is represented very close to completely consistently, and as aforementioned, the 77-odd-limit subset of that odd-limit is perfectly consistent, to which a variety of odds can be added that keep perfect consistency, but for comprehensiveness and practical use as a temperament approximating the low-to-mid end of the harmonic series, we consider a larger odd-limit than that which seeks to be more complete. | ||
There | There are 884 interval pairs in that [[odd-limit]] (the [[41-limit]] add-73 add-89 add-101 add-109 add-113 123-odd-limit), where "pairs" refers to that each interval has an [[octave complement]] with equal and opposite error. | ||
That odd | That odd limit can be described explicitly as the | ||
{1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 25, 27, 29, 31, 33, 35, 37, 39, 41, 45, 49, 51, 55, 57, 63, 65, 69, 73, 75, 77, 81, 85, 87, 89, 91, 93, 95, 99, 101, 105, 109, 111, 113, 115, 117, 119, 121, 123}-odd-limit | {1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 25, 27, 29, 31, 33, 35, 37, 39, 41, 45, 49, 51, 55, 57, 63, 65, 69, 73, 75, 77, 81, 85, 87, 89, 91, 93, 95, 99, 101, 105, 109, 111, 113, 115, 117, 119, 121, 123}-odd-limit | ||
or equivalently, as the [[diamond function]] applied to that set of odds. | |||
We can also express that odd-limit as the 123-odd-limit minus only the following twelve prime odds: {43, 47, 53, 59, 61, 67, 71, 79, 83, 97, 103, 107}. | We can also express that odd-limit as the 123-odd-limit minus only the following twelve prime odds: {43, 47, 53, 59, 61, 67, 71, 79, 83, 97, 103, 107}. | ||
Of those 884 interval pairs, only 42 interval pairs (<4.8%) are inconsistent | Of those 884 interval pairs, only 42 interval pairs (< 4.8%) are inconsistent, not mapped to the nearest interval of 311edo but to the second-nearest interval. | ||
Reduced to the lower half of the octave, these intervals, from smallest to largest, are: | |||
101/100, 100/99, 82/81, 121/119, 119/117, 95/93, 87/85, 124/119, 85/81, 101/95, 100/93, 85/78, 93/85, 119/108, 93/82, 81/70, 138/119, 136/117, 99/85, 117/100, 95/81, 119/101, 101/85, 81/68, 140/117, 119/99, 117/95, 85/69, 100/81, 108/85, 119/93, 85/66, 156/119, 93/70, 162/119, 93/68, 119/87, 85/62, 117/85, 140/101, 164/117, 170/121 | 101/100, 100/99, 82/81, 121/119, 119/117, 95/93, 87/85, 124/119, 85/81, 101/95, 100/93, 85/78, 93/85, 119/108, 93/82, 81/70, 138/119, 136/117, 99/85, 117/100, 95/81, 119/101, 101/85, 81/68, 140/117, 119/99, 117/95, 85/69, 100/81, 108/85, 119/93, 85/66, 156/119, 93/70, 162/119, 93/68, 119/87, 85/62, 117/85, 140/101, 164/117, 170/121 | ||
and their octave complements. | |||
Of them, only 6 interval pairs (119/117, 85/81, 93/85, 101/85, 119/93, 117/85) are more than 10% inconsistent, which is to say, all 36 of the other inconsistent intervals have less than 60% of a step of | Of them, only 6 interval pairs (119/117, 85/81, 93/85, 101/85, 119/93, 117/85) are more than 10% inconsistent, which is to say, all 36 of the other inconsistent intervals have less than 60% of a step of 311edo of error relative to where they are mapped in 311edo by the patent val, which is to say less than 3/5 = 60% [[relative interval error]], which is equal to 2.3{{cent}}. | ||
The 6 highest-error intervals mentioned instead have less than 2/3 = | The 6 highest-error intervals mentioned instead have less than 2/3 = 67% [[relative interval error]]. | ||
The below table was generated by | The below table was generated by a simple Python 3 script to print it in plaintext using [[User: Godtone #My Python 3 code|Godtone's code]] to simplify certain steps. | ||
It should be noted that while almost all intervals shown in the table are intervals of the 123-odd-limit restricted to the aforementioned prime subgroup, the [[square-particular]]s up to [[1681/1680|S41 = (41/40)/(42/41)]] were added manually for completeness and reference in understanding the mapping of the [[41-odd-limit]] by | It should be noted that while almost all intervals shown in the table are intervals of the 123-odd-limit restricted to the aforementioned prime subgroup, the [[square-particular]]s up to [[1681/1680|S41 = (41/40)/(42/41)]] were added manually for completeness and reference in understanding the mapping of the [[41-odd-limit]] by 311edo. Therefore, the very beginning of the table (from 0\311 to 3\311 inclusive) is the only part that is not algorithmically generated. | ||
{| class="mw-collapsible mw-collapsed wikitable center-1 center-2 center-3" | {| class="mw-collapsible mw-collapsed wikitable center-1 center-2 center-3" | ||
|+ style=white-space:nowrap | Table of 311edo intervals | |+ style=white-space:nowrap | Table of 311edo intervals | ||
! Genes* | |||
! Cents | |||
! Marks | |||
! Approximate Intervals† | |||
|- | |- | ||
| 0 | | 0 | ||
| Line 1,615: | Line 1,615: | ||
| '''2/1''' | | '''2/1''' | ||
|} | |} | ||
< | <nowiki>*</nowiki> ''gene'' is the [[interval size measure]] for 311edo, named after [[Gene Ward Smith]]<br> | ||
† odd harmonics and subharmonics are in bold and linked, inconsistent intervals in italics, all [[23-limit]] intervals linked) | |||
== Notation == | == Notation == | ||