Periodic scale: Difference between revisions

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=== Classes ===
=== Classes ===
A class is a category of all intervals spanning a specified number of scale degrees, such as "2-mosstep", "3-mosstep" etc in a MOS, or the generalization to any kind of scale.
A class is a category of all intervals spanning a specified number of scale degrees, such as seconds, thirds, fourths etc in diatonic, or the generalization to any kind of scale.


In mathematical terms, we can define a function class(''k'') on the integers which gives sets representing the ''generic intervals'' of a periodic scale. For some integer ''k'', the set class(''k'') consists of all intervals <math>s[k+i] - s[i]</math>. Since ''s'' is quasiperiodic, class(''P'') only contains the period ''O'', but the rest may contain multiple intervals.
In mathematical terms, we can define a function class(''k'') on the integers which gives sets representing the ''generic intervals'' of a periodic scale. For some integer ''k'', the set class(''k'') consists of all intervals <math>s[k+i] - s[i]</math>. Since ''s'' is quasiperiodic, class(''P'') only contains the period ''O'', but the rest may contain multiple intervals.