Stretching and compression

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Stretching and compression are (usually logarithmic) operations that can be done on melodies, scales, or chords. Stretching can be called tens and compression can be called tract; these morphemes may be prefixed to chords or scales to indicate stretching and compression.

Scales

A scale pattern can be compressed by inserting a(n arbitrary but usually small) step size; this is how oneirotonic is obtained from MOS diatonic (LLsLLLs -> LLsLsLLs), and similarly pinedye (LLmLLLm -> LLmLLsLm). A scale pattern may be stretched by removing a step (MOS diatonic LLsLLLs -> machinoid LLLLLs) or making it smaller (MOS diatonic LLsLLLs -> smitonic LLsLsLs).

Chords

Stretched versions of chords can be indicated by using the prefix tens-, and compressed versions of chords can be indicated by using the prefix tract-. (Example: oneirotonic tract-diatonic chords such as the tract-major triad which is 0s-M2s-M4s in TAMNAMS notation)