Scale diversity: Difference between revisions

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Properties:
Properties:


<ul><li>Degenerate scales (scales with no intervals smaller than an octave and larger than a unison) have a diversity of 0.</li><li>EDOs have a diversity of 1.</li><li>Div(S) ≥ 0 since there are no intervals larger than an octave.</li></ul>
* Degenerate scales (scales with no intervals smaller than an octave and larger than a unison) have a diversity of 0.
* EDOs have a diversity of 1.
* Div(S) ≥ 0 since there are no intervals larger than an octave.


=Definition:=
=Definition:=
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N is the cardinality of S.
N is the cardinality of S.


dia(S) is the [[Diamonds|diamond]] function.
dia(S) is the [[diamond function]].


sort(S) returns a tuple with all of the elements of S in non-decreasing order.
sort(S) returns a tuple with all of the elements of S in non-decreasing order.
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steps(T) returns a multiset whose elements are the consecutive differences of elements in a tuple T
steps(T) returns a multiset whose elements are the consecutive differences of elements in a tuple T


The scale diversity measure was proposed by [[Ryan_Avella|Ryan Avella]].
The scale diversity measure was proposed by [[Ryan Avella]].
[[Category:math]]
 
[[Category:scale]]
[[Category:Math]]
[[Category:theory]]
[[Category:Scale]]
{{todo|clarify}}

Latest revision as of 16:32, 26 February 2022

Diversity is a scale measurement which categorizes scales according to the "diversity" of available intervals. As a general rule of thumb, scales with many unique interval sizes will have a high diversity. Similarly, scales with many redundant intervals will be assigned a low diversity rating.

Properties:

  • Degenerate scales (scales with no intervals smaller than an octave and larger than a unison) have a diversity of 0.
  • EDOs have a diversity of 1.
  • Div(S) ≥ 0 since there are no intervals larger than an octave.

Definition:

[math]\displaystyle{ \mathrm{Div} (S) = - \log_N \left( \sum \limits_{x \in X} x^2 \right) }[/math]

[math]\displaystyle{ X = \mathrm{steps} ( \mathrm{sort} ( \mathrm{dia} (S))) }[/math]

Where:

S is a multiset.

N is the cardinality of S.

dia(S) is the diamond function.

sort(S) returns a tuple with all of the elements of S in non-decreasing order.

steps(T) returns a multiset whose elements are the consecutive differences of elements in a tuple T

The scale diversity measure was proposed by Ryan Avella.