Talk:Periodic scale: Difference between revisions
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I'd like the page to mention the two ways of writing a periodic scale as a function: | I'd like the page to mention the two ways of writing a periodic scale as a function: | ||
# The ''cumulative form'' (the formalization on the article), a monotone increasing function <math>S: \mathbb{Z}\to \mathbb{R}</math> such that ''S''(0) = '''0''' (unison) and ''S''(''k'' len(''S'')) = ''k'''''E''' where '''E''' is the equave. | # The ''cumulative form'' (the formalization on the article), a monotone increasing function <math>S: \mathbb{Z}\to \mathbb{R}</math> such that ''S''(0) = '''0''' (unison) and ''S''(''k'' len(''S'')) = ''k'''''E''' where '''E''' is the equave. | ||
# The ''step form'', related to the above via Δ''S''(''k'') = ''S''(''k'' + 1) − ''S''(''k''), which is nonnegative and periodic in the usual math sense. | # The ''step form'', the sequence of steps in the scale, related to the above via Δ''S''(''k'') = ''S''(''k'' + 1) − ''S''(''k''), which is nonnegative and periodic in the usual math sense. | ||
We can also mention scales considered more abstractly, <math>S: \mathbb{Z}\to A</math> where ''A'' is any abelian group such as <math>\mathbb{R}</math> (log-frequency interval space), a free abelian group on steps, or a JI subgroup. | We can also mention scales considered more abstractly, <math>S: \mathbb{Z}\to A</math> where ''A'' is any abelian group such as <math>\mathbb{R}</math> (log-frequency interval space), a free abelian group on steps, or a JI subgroup. | ||
[[User:Inthar|Inthar]] ([[User talk:Inthar|talk]]) 16:33, 8 February 2024 (UTC) | [[User:Inthar|Inthar]] ([[User talk:Inthar|talk]]) 16:33, 8 February 2024 (UTC) | ||