Operations on MOSes: Difference between revisions
mNo edit summary |
|||
Line 1: | Line 1: | ||
== Sisterization == | == Sisterization == | ||
'''Sisterization''' is the operation of taking a MOS pattern xL ys and reversing the roles of large and small steps, thus creating a yL xs pattern, called the ''sister'' of xL ys. | '''Sisterization''' is the operation of taking a MOS pattern xL ys and reversing the roles of large and small steps, thus creating a yL xs pattern, called the ''sister'' of xL ys. It is called thus because they share the same MOS as a subset (for example, [[5L 2s]] and [[2L 5s]] both have [[2L 3s]] subsets), which is the parent on the tree of MOS patterns (closely related to the Stern-Brocot tree). A sister of a MOS pattern are often denoted with the prefix ''anti-''. | ||
If xL ys has a generator range between a\x and b\(x+y) (it always holds that a < b), then its | If xL ys has a generator range between a\x and b\(x+y) (it always holds that a < b), then its sister yL xs has a generator range between b\(x+y) and (b-a)\y. | ||
Examples: | Examples: | ||
* [[2L 5s]] is the sister of [[5L 2s]] (anti-diatonic) | * [[2L 5s]] is the sister of [[5L 2s]] (anti-diatonic) | ||
* [[3L 5s]] is the sister [[5L 3s]] (anti-oneirotonic) | * [[3L 5s]] is the sister [[5L 3s]] (anti-oneirotonic) | ||
== Neutralization == | == Neutralization == | ||
'''Neutralization''' is the operation of taking a MOS pattern and creating a new MOS pattern with the same number of notes, but with some of the steps replaced with what would be "neutral seconds" according to the original MOS pattern. | '''Neutralization''' is the operation of taking a MOS pattern and creating a new MOS pattern with the same number of notes, but with some of the steps replaced with what would be "neutral seconds" according to the original MOS pattern. |