Simple/Compound Time Signature Classifier

Classify explicit notated beat groups rather than assume every divisible-by-three numerator is compound (3/4 may be three single quarter beats); mixed/additive grouping retained.

Description

Meter subdivision describes the units within each declared beat.

Meter subdivision describes the units within each declared beat. The signature numerator alone does not establish the grouping.^[1]

Enter integer numerator 1–32 and denominator from 1,2,4,8,16,32,64 and 1–32 integer beat groups 1–4 whose sum equals numerator. Return subdivision class, beat count and uniform-group flag.

When to use Simple/Compound Time Signature Classifier

Use Simple/Compound Time Signature Classifier when you need to evaluate the supplied records under the calculation and evidence rules below. Grouping is caller-declared, not inferred from notation or audio. Compound classification does not determine duple/triple pulse count.

Enter the written notes, explicit grouping, pitch observations or supported chord tokens requested. Keep scientific octaves, accidentals and caller evidence consistent.

How to use Simple/Compound Time Signature Classifier and understand its results

Enter the written notes, explicit grouping, pitch observations or supported chord tokens requested. Keep scientific octaves, accidentals and caller evidence consistent.
Enter signatureNumerator, signatureDenominator, declaredBeatGroups using the field table and calculation rules, then run the tool.
Read beatDivisionClass, notatedBeatCount, uniformBeatGrouping. The explanation below defines the units, signs, ordering and any flags or placeholder values.
If the tool reports an input issue, correct the values and run it again. Apply the stated assumptions when interpreting a successfully returned result.

Input field	Meaning	Value type; see rules below	Requirement
signatureNumerator	Signature numerator	number	Required
signatureDenominator	Signature denominator	number	Required
declaredBeatGroups	Declared beat groups	list of number	Required

Enter integer numerator 1–32 and denominator from 1,2,4,8,16,32,64 and 1–32 integer beat groups 1–4 whose sum equals numerator. Return subdivision class, beat count and uniform-group flag.

all groups=3→compound; uniform groups in 1,2,4→simple; otherwise mixed-additive

Units, indexing, boundary conditions and exceptional cases are defined in the calculation rules above.

Output field	Meaning	Value type
beatDivisionClass	Beat division class	string
notatedBeatCount	Notated beat count	number
uniformBeatGrouping	Uniform beat grouping	boolean

json

{
  "input": {
    "signatureNumerator": 6,
    "signatureDenominator": 8,
    "declaredBeatGroups": [
      3,
      3
    ]
  },
  "output": {
    "beatDivisionClass": "compound",
    "notatedBeatCount": 2,
    "uniformBeatGrouping": true
  }
}

Limitations and assumptions

Grouping is caller-declared, not inferred from notation or audio. Compound classification does not determine duple/triple pulse count.

Numeric inputs, where present, must be finite. Follow the calculation-specific rules for overflow, underflow and exceptional cases. Numeric lists are limited to 10,000 entries; string lists to 128 strings of at most 128 characters each. The rules above may impose smaller limits. Missing required fields, extra fields, wrong value types and violations of the calculation rules are input errors. A successfully returned false flag is an evaluated outcome; its meaning is explained above.

Alternative or Complementary methods

Use Duple/Triple/Quadruple Meter Classifier: Pulse count and beat subdivision answer different meter questions. Unequal groups can form an additive meter under the same signature. For a complementary task, use Major Scale Pattern Checker: The major scale has seven ordered steps including the return to the octave. Correct membership alone does not verify this ordered pattern.

References

Simple/Compound Time Signature Classifier — tool.io

Similar or alternative tools

Duple/Triple/Quadruple Meter Classifier
Pulse count and beat subdivision answer different meter questions. Unequal groups can form an additive meter under the same signature.
Major Scale Pattern Checker
The major scale has seven ordered steps including the return to the octave. Correct membership alone does not verify this ordered pattern.