Class Scale

Musical scale consisting of Interval instances repeated at octaves or generic equaves.

Constructors

constructor

new Scale(intervals, equave, baseFrequency): Scale
Construct a new musical scale.
Parameters
- intervals: Interval[]
  Intervals of the scale including 1/1, but not the interval of equivalence.
- equave: Interval
  The interval of equivalence.
- baseFrequency: number
  Base frequency of plain 1/1.
Returns Scale
- Defined in scale.ts:24

Properties

baseFrequency

baseFrequency: number

equave

equave: Interval

intervals

intervals: Interval[]

Accessors

numberOfComponents

get numberOfComponents(): number
Number of components in the monzo vector part of the scale's intervals.

Returns number
- Defined in scale.ts:568

size

get size(): number
Number of intervals in the scale.

Returns number
- Defined in scale.ts:563

Methods

approximateEqualTemperament

approximateEqualTemperament(divisions): Scale
Create a new scale where every interval is replace with the closest approximation in the given EDO/EDJI.
Parameters
- divisions: number
  Number of divisions per equave.
Returns Scale
A new scale of approximations in equal temperament.
- Defined in scale.ts:989

approximateHarmonics

approximateHarmonics(denominator): Scale
Create a new scale where every interval is replace with the closest approximation in a harmonic series.
Parameters
- denominator: number
  Denominator/root of the harmonic series slice.
Returns Scale
A new scale of harmonic approximations.
- Defined in scale.ts:1018

approximateSubharmonics

approximateSubharmonics(numerator): Scale
Create a new scale where every interval is replace with the closest approximation in a subharmonic series.
Parameters
- numerator: number
  Numerator/root of the subharmonic series slice.
Returns Scale
A new scale of subharmonic approximations.
- Defined in scale.ts:1031

asType

asType(type, options?): Scale
Convert the intervals in the scale to another type.
Parameters
- type: IntervalType
  The new formatting type.
- Optional options: IntervalOptions
  New formatting options.
Returns Scale
A new scale of intervals with the new formatting type and options.
- Defined in scale.ts:1058

concat

concat(other, deep?): Scale
Create a new scale by concatenating this one with another. Duplicates unison and other scale degrees if present.
Parameters
- other: Scale
  Another scale with the same equave and base frequency.
- deep: boolean = false
  Create new copies of the Interval instances.
Returns Scale
A new scale that includes all the intervals from both scales.
- Defined in scale.ts:899

filter

filter(): Scale
Remove intervals that do not fit between the unison and the equave.

Returns Scale
A variant of the scale where all intervals fit inside the equave.
- Defined in scale.ts:720

getCents

getCents(index): number
Obtain the total cents of an interval in the scale (repeats at equaves).
Parameters
- index: number
  Zero-based index of the interval.
Returns number
Cents associated with the given index.
- Defined in scale.ts:602

getFrequency

getFrequency(index): number
Obtain the frequency of an interval in the scale (repeats at equaves).
Parameters
- index: number
  Zero-based index of the interval.
Returns number
The frequency of an interval in the scale with equaves factored in as necessary.
- Defined in scale.ts:629

getFrequencyRange

getFrequencyRange(start, end): number[]
Obtain a range of frequencies in the scale. More efficient to compute than getting individual frequencies.
Parameters
- start: number
  The smallest index to include.
- end: number
  The end point end itself not included.
Returns number[]
An array of frequencies corresponding to the specified range.
- Defined in scale.ts:640

getInterval

getInterval(index): Interval
Obtain an Interval of the scale (repeats at equaves).
Parameters
- index: number
  Zero-based index of the interval.
Returns Interval
An interval of the scale with equaves added as necessary.
- Defined in scale.ts:577

getMonzo

getMonzo(index): ExtendedMonzo
Obtain the ExtendedMonzo of an interval in the scale (repeats at equaves).
Parameters
- index: number
  Zero-based index of the interval.
Returns ExtendedMonzo
An ExtendedMonzo of the scale with equaves added as necessary.
- Defined in scale.ts:591

getName

getName(index): string
Obtain the name of an interval in the scale.
Parameters
- index: number
  Zero-based index of the interval.
Returns string
Name of an on interval in the scale without equaves factored in. The unison is named after the equave.
- Defined in scale.ts:663

getRatio

getRatio(index): number
Obtain the ratio of an interval in the scale (repeats at equaves).
Parameters
- index: number
  Zero-based index of the interval.
Returns number
Ratio associated with the given index.
- Defined in scale.ts:615

head

head(end): Scale
Obtain a subset of the scale up to the given index.
Parameters
- end: number
  Last index to include.
Returns Scale
A new scale with only the specified subset included.
- Defined in scale.ts:812

insertAfter

insertAfter(degree, interval, deep?): Scale
Create a new scale with a new interval inserted.
Parameters
- degree: number
  Degree to insert after.
- interval: Interval
  Interval to insert.
- deep: boolean = false
  Create new copies of the Interval instances.
Returns Scale
A new scale with the new interval inserted.
- Defined in scale.ts:971

invert

invert(): Scale
Invert the intervals in the scale.

Returns Scale
A new inverted scale.
- Defined in scale.ts:834

merge

merge(other): Scale
Merge this scale with another, removing duplicates and sorting the result.
Parameters
- other: Scale
  Another scale.
Returns Scale
A new scale with intervals from both without duplicates.
- Defined in scale.ts:941

mergeOptions

mergeOptions(options): Scale
Merge existing formatting options with new ones.
Parameters
- options: IntervalOptions
  New options. Takes priority over existing keys.
Returns Scale
A new scale of intervals with the new formatting options.
- Defined in scale.ts:1044

reduce

reduce(): Scale
Reduce intervals in the scale by the equave.

Returns Scale
A variant of the scale where all intervals fit inside the equave.
- Defined in scale.ts:709

removeDuplicatesInPlace

removeDuplicatesInPlace(): Scale
Remove duplicate intervals in-place.

Returns Scale
This scale.
- Defined in scale.ts:921

repeat

repeat(numRepeats?, deep?): Scale
Repeat the scale at the equave and replace the old equave. Produces the same frequencies as the old scale.
Parameters
- numRepeats: number = 2
  Number of repeats.
- deep: boolean = false
  Create new copies of the Interval instances.
Returns Scale
A new scale repeated numRepeats times.
- Defined in scale.ts:735

replaceDegree

replaceDegree(degree, replacement, deep?): Scale
Create a new scale with a degree of the scale replaced by another.
Parameters
- degree: number
  Index of the interval to replace.
- replacement: Interval
  The interval to replace with.
- deep: boolean = false
  Create new copies of the Interval instances.
Returns Scale
A new scale with the given interval spliced in.
- Defined in scale.ts:878

rotate

rotate(numSteps?): Scale
Rotate the scale to a new mode.
Parameters
- numSteps: number = 1
  Number of steps to rotate by.
Returns Scale
Another mode of the scale.
- Defined in scale.ts:766

sortInPlace

sortInPlace(): Scale
Sort the scale in-place.

Returns Scale
The scale with intervals sorted from smallest to largest without touching the equave.
- Defined in scale.ts:675

sorted

sorted(deep?): Scale
Construct a sorted copy of the scale. scale in-place.
Parameters
- deep: boolean = false
  Create new copies of the intervals instead just a new array with the old instances.
Returns Scale
The scale with intervals sorted from smallest to largest without touching the equave.
- Defined in scale.ts:694

stretch

stretch(scalar): Scale
Stretch the scale using the given scaling factor.
Parameters
- scalar: number
  The scaling factor in pitch-space.
Returns Scale
A new streched scale.
- Defined in scale.ts:821

subset

subset(indices, deep?): Scale
Obtain a subset of the scale.
Parameters
- indices: number[]
  Indices of the intervals to include.
- deep: boolean = false
  Create new copies of the Interval instances.
Returns Scale
A new scale with only the specified subset included.
- Defined in scale.ts:791

toStrings

toStrings(): string[]
Convert scale intervals to strings. Also known as reverse parsing.

Returns string[]
An array of textual scale lines.
- Defined in scale.ts:1071

transpose

transpose(offset): Scale
Transpose the scale. WARNING: Moves the unison as well and doesn't reduce by the equave.
Parameters
- offset: Interval
  Interval to transpose by.
Returns Scale
A new transposed scale.
- Defined in scale.ts:866

transposeDegree

transposeDegree(degree, offset, deep?): Scale
Create a new scale where a single degree has been transposed.
Parameters
- degree: number
  Degree to transpose.
- offset: Interval
  Amount to transpose by.
- deep: boolean = false
  Create new copies of the Interval instances.
Returns Scale
A new scale with a transposed degree.
- Defined in scale.ts:952

variant

variant(intervals): Scale
Construct a variant of the scale with new intervals, but the same equave and base frequency.
Parameters
- intervals: Interval[]
  New intervals for the scale.
Returns Scale
A new scale with new intervals.
- Defined in scale.ts:685

vary

vary(maxCents, varyEquave?): Scale
Add random variation to the intervals in the scale.
Parameters
- maxCents: number
  Maximum deviation in cents.
- varyEquave: boolean = false
  Apply variation the the interval of equivalence.
Returns Scale
A new scale with variance added.
- Defined in scale.ts:848

`Static` fromChord

fromChord(chord, baseFrequency?): Scale
Construct a musical scale from a chord in (assumed) root position.
Parameters
- chord: Interval[]
  Array of intervals in the chord not neccessarily starting from 1/1.
- baseFrequency: number = 440
  Base frequency of unison/root note of the chord.
Returns Scale
New musical scale transposed to start from 1/1.
- Defined in scale.ts:277

`Static` fromCombinations

fromCombinations(factors, numElements, addUnity, equave, baseFrequency?): Scale
Construct a musical scale from a combination product set.
Parameters
- factors: Interval[] | Set<Interval>
  Factors in the original set.
- numElements: number
  Number of elements to multiply together in frequency-space in each combination.
- addUnity: boolean
  Add 1/1 into the scale along with the combinations. If false the scale will be transposed to include a combination at unison.
- equave: Interval
  Interval of equivalence.
- baseFrequency: number = 440
  Base frequency of unison or the least product before reduction by the equave.
Returns Scale
A new combination product set reduced to fit inside the equave and sorted by size.
- Defined in scale.ts:296

`Static` fromCrossPolytope

fromCrossPolytope(basis, addUnity, equave, baseFrequency?): Scale
Construct a new musical scale from an array of intervals and their inverses.
Parameters
- basis: Interval[] | Set<Interval>
  Basis intervals of the cross polytope.
- addUnity: boolean
  Include the center of the polytope.
- equave: Interval
  Interval of equivalence.
- baseFrequency: number = 440
  Base frequency of 1/1 or the least of interval of the polytope before reduction by the equave.
Returns Scale
A new musical in the form of a generalized octahedron in monzo space.
- Defined in scale.ts:377

`Static` fromCube

fromCube(basis, equave, baseFrequency?): Scale
Parameters
- basis: Interval[]
- equave: Interval
- baseFrequency: number = 440
Returns Scale
- Defined in scale.ts:360

`Static` fromDwarf

fromDwarf(val, equave, numberOfComponents, baseFrequency?): Scale
Construct a new Dwarf scale.
Parameters
- val: number
  Patent val.
- equave: number
  Interval of equivalence. Anything other than 2 results in a generalized scale.
- numberOfComponents: number
  Number of components in monzo vector parts.
- baseFrequency: number = 440
  Base frequency of 1/1.
Returns Scale
A new Dwarf scale.
- Defined in scale.ts:493

`Static` fromEqualTemperament

fromEqualTemperament(divisions, equave, numberOfComponents, baseFrequency?): Scale
Construct a new musical scale that equally divides an interval in pitch-space.
Parameters
- divisions: number
  Number of notes per equave.
- equave: Fraction
  Equave to divide.
- numberOfComponents: number
  Number of components in monzo vector parts.
- baseFrequency: number = 440
  Base frequency of unison.
Returns Scale
A new musical scale that equally divides the given equave.

Throws
An error if divisions is not an integer.
- Defined in scale.ts:55

`Static` fromEqualTemperamentSubset

fromEqualTemperamentSubset(steps, equave, baseFrequency?): Scale
Construct a new musical scale from a subset of an equal temperament.
Parameters
- steps: number[]
  Intervals to include in the scale. The last step determines the EDO / ED of EDJI.
- equave: Interval
  Interval to equally divide.
- baseFrequency: number = 440
  Base frequency of unison.
Returns Scale
A new musical scale consisting of s1\N<equave>, s2\N<equave>, ..., N\N<equave>.
- Defined in scale.ts:544

`Static` fromEulerGenus

fromEulerGenus(guideTone, equave, numberOfComponents, baseFrequency?): Scale
Construct a new Euler-Fokker genus.
Parameters
- guideTone: number
  Positive integer whose positive factors make up the scale.
- equave: number
  Interval of equivalence. Anything other than 2 results in a generalized genus.
- numberOfComponents: number
  Number of components in monzo vector parts.
- baseFrequency: number = 440
  Base frequency of 1/1.
Returns Scale
A new Euler-Fokker scale.
- Defined in scale.ts:459

`Static` fromFractionalTemperament

fromFractionalTemperament(divisions, equaveCents, numberOfComponents, baseFrequency?): Scale
Construct a new musical scale that equally divides an interval in pitch-space.
Parameters
- divisions: number
  Number of notes per equave. Doesn't have to be an integer.
- equaveCents: number
  Size of the equave to divide in cents.
- numberOfComponents: number
  Number of components in monzo vector parts.
- baseFrequency: number = 440
  Base frequency of unison.
Returns Scale
A new musical scale that equally divides the given equave.
- Defined in scale.ts:100

`Static` fromHarmonicSeries

fromHarmonicSeries(denominator, greatestNumerator, numberOfComponents, baseFrequency?): Scale
Construct a new musical scale from a slice of the harmonic series.
Parameters
- denominator: number
  Denominator of every interval in the scale.
- greatestNumerator: number
  The largest numerator of an interval to include in the scale.
- numberOfComponents: number
  Number of components in monzo vector parts.
- baseFrequency: number = 440
  Base frequency of unison.
Returns Scale
A new musical scale of the form denominator / denominator, (denominator + 1) / denominator, ..., greatestNumerator / denominator.
- Defined in scale.ts:193

`Static` fromIntervalArray

fromIntervalArray(intervals, baseFrequency?): Scale
Construct a new musical scale from an array of intervals.
Parameters
- intervals: Interval[]
  Intervals of the scale including the interval of equivalence, but not 1/1.
- baseFrequency: number = 440
  Base frequency of plain 1/1.
Returns Scale
A new musical scale with the given intervals.
- Defined in scale.ts:36

`Static` fromLattice

fromLattice(basis, dimensions, equave, baseFrequency?): Scale
Construct a new musical scale from finite slice of a multi-dimensional interval lattice.
Parameters
- basis: Interval[]
  Basis intervals of the lattice.
- dimensions: number[]
  Dimensions of the slice. Each integer determines how many times to stack a basis vector.
- equave: Interval
  Interval of equivalence.
- baseFrequency: number = 440
  Base frequency of unison.
Returns Scale
A new musical scale of the lattice slice reduced by the equave and sorted by sice.
- Defined in scale.ts:338

`Static` fromOctaplex

fromOctaplex(basis, addUnity, equave, baseFrequency?): Scale
Construct a new musical scale in the shape of a 4D octaplex/24-cell.
Parameters
- basis: Interval[] | Set<Interval>
  The four basis intervals of the octaplex.
- addUnity: boolean
  Include the center of the octaplex.
- equave: Interval
  Interval of equivalence.
- baseFrequency: number = 440
  Base frequency of 1/1 or the least of interval of the octaplex before reduction by the equave.
Returns Scale
A new musical scale in the form of an octaplex in monzo space.
- Defined in scale.ts:411

`Static` fromRank2

fromRank2(generator, period, size, down, numPeriods?, baseFrequency?): Scale
Construct a new musical scale by stacking a generating interval against a period.
Parameters
- generator: Interval
  The generating interval such as a fifth.
- period: Interval
  The period of repetition such as a tritone.
- size: number
  Size of the scale. Must be a multiple of the number of periods per equave.
- down: number
  Number of steps to stack down. Stacking is distributed among the periods so down must be a multiple of the number of periods per equave.
- numPeriods: number = 1
  Number of periods per equave. (Equave = period * numPeriods, in pitch-space)
- baseFrequency: number = 440
  Base frequency of unison.
Returns Scale
A new musical scale resulting from stacking the generator, reducing by the period and stacking the result to fill the equave.
- Defined in scale.ts:135

`Static` fromSubharmonicSeries

fromSubharmonicSeries(numerator, leastDenominator, numberOfComponents, baseFrequency?): Scale
Construct a new musical scale from a slice of the subharmonic series.
Parameters
- numerator: number
  Numerator of every interval in the scale.
- leastDenominator: number
  The smallest denominator of an interval to include in the scale.
- numberOfComponents: number
  Number of components in monzo vector parts.
- baseFrequency: number = 440
  Base frequency of unison.
Returns Scale
A new musical scale of the form numerator / numerator, numerator / (numerator - 1), ..., numerator / leastDenominator.
- Defined in scale.ts:237

Class Scale

Index

Constructors

Properties

Accessors

Methods

Constructors

constructor

Parameters

Returns Scale

Properties

baseFrequency

equave

intervals

Accessors

numberOfComponents

Returns number

size

Returns number

Methods

approximateEqualTemperament

Parameters

Returns Scale

approximateHarmonics

Parameters

Returns Scale

approximateSubharmonics

Parameters

Returns Scale

asType

Parameters

Returns Scale

concat

Parameters

Returns Scale

filter

Returns Scale

getCents

Parameters

Returns number

getFrequency

Parameters

Returns number

getFrequencyRange

Parameters

Returns number[]

getInterval

Parameters

Returns Interval

getMonzo

Parameters

Returns ExtendedMonzo

getName

Parameters

Returns string

getRatio

Parameters

Returns number

head

Parameters

Returns Scale

insertAfter

Parameters

Returns Scale

invert

Returns Scale

merge

Parameters

Returns Scale

mergeOptions

Parameters

Returns Scale

reduce

Returns Scale

removeDuplicatesInPlace

Returns Scale

repeat

Parameters

Returns Scale

replaceDegree

`Static` fromChord

`Static` fromCombinations

`Static` fromCrossPolytope

`Static` fromCube

`Static` fromDwarf

`Static` fromEqualTemperament

`Static` fromEqualTemperamentSubset

`Static` fromEulerGenus

`Static` fromFractionalTemperament

`Static` fromHarmonicSeries

`Static` fromIntervalArray

`Static` fromLattice

`Static` fromOctaplex