Get a mode of a scale type by shifting the order of its intervals. For example, the Phrygian mode is the third mode of the major scale:

mode 3 major == phrygian

Note: like many numbers in music theory, modes are 1-based; 2 means the second mode of the scale type. 0 and negative integers are ignored.

Get the intervals contained in the scale type:

toList major
    == [ Interval.perfectUnison
       , Interval.majorSecond
       , Interval.majorThird
       , Interval.perfectFourth
       , Interval.perfectFifth
       , Interval.majorSixth
       , Interval.majorSeventh
       ]

Same as ionian

Also known as the "natural minor" scale. Same as aeolian

Define a custom scale type with 5 degrees:

customPentatonic
    { rootToSecond = Interval.minorThird
    , rootToThird = Interval.perfectFourth
    , rootToFourth = Interval.perfectFifth
    , rootToFifth = Interval.minorSeventh
    }
    == minorPentatonic

Define a custom scale type with 6 degrees:

customHexatonic
    { rootToSecond = Interval.majorSecond
    , rootToThird = Interval.majorThird
    , rootToFourth = Interval.augmentedFourth
    , rootToFifth = Interval.minorSixth
    , rootToSixth = Interval.minorSeventh
    }
    == wholeTone

Define a custom scale type with 7 degrees:

customHeptatonic
    { rootToSecond = Interval.majorSecond
    , rootToThird = Interval.minorThird
    , rootToFourth = Interval.perfectFourth
    , rootToFifth = Interval.perfectFifth
    , rootToSixth = Interval.majorSixth
    , rootToSeventh = Interval.minorSeventh
    }
    == dorian

Define a custom scale type with 8 degrees:

customOctatonic
    { rootToSecond = Interval.majorSecond
    , rootToThird = Interval.minorThird
    , rootToFourth = Interval.perfectFourth
    , rootToFifth = Interval.diminishedFifth
    , rootToSixth = Interval.minorSixth
    , rootToSeventh = Interval.majorSixth
    , rootToEighth = Interval.majorSeventh
    }
    == diminishedWholeToneHalfTone