Secondary Dominant Target Lookup

Parse secondary V/V7 function over explicit major-key Roman target and derive spelled target/dominant root; nested functions/diminished targets rejected, no inferred resolution from chord alone.

Description

A secondary dominant is spelled a perfect fifth above a declared target.

A secondary dominant is spelled a perfect fifth above a declared target. The slash target carries Roman degree and alteration relative to a major tonic.^[1]

Enter pitch-class major tonic and exact V/target or V7/target with a simple Roman target and at most double alteration. Reject diminished targets; return target token/root and dominant root/symbol.

When to use Secondary Dominant Target Lookup

Use Secondary Dominant Target Lookup when you need to evaluate the supplied records under the calculation and evidence rules below. Nested functions, harmonic resolution and tonicization evidence are excluded.

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

How to use Secondary Dominant Target Lookup 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 majorTonic, secondaryFunction using the field table and calculation rules, then run the tool.
Read targetRomanToken, targetChordRoot, secondaryDominantRoot, secondaryDominantSymbol. 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
majorTonic	Major tonic	string	Required
secondaryFunction	Secondary function	string	Required

Enter pitch-class major tonic and exact V/target or V7/target with a simple Roman target and at most double alteration. Reject diminished targets; return target token/root and dominant root/symbol.

target=majorScaleDegree+alteration; dominant=target+four letter steps/seven semitones

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

Output field	Meaning	Value type
targetRomanToken	Target roman token	string
targetChordRoot	Target chord root	string
secondaryDominantRoot	Secondary dominant root	string
secondaryDominantSymbol	Secondary dominant symbol	string

json

{
  "input": {
    "majorTonic": "C",
    "secondaryFunction": "V7/ii"
  },
  "output": {
    "targetRomanToken": "ii",
    "targetChordRoot": "D",
    "secondaryDominantRoot": "A",
    "secondaryDominantSymbol": "A7"
  }
}

Limitations and assumptions

Nested functions, harmonic resolution and tonicization evidence are excluded.

Numeric inputs, where present, must be finite. Follow the calculation-specific rules for overflow, underflow and exceptional cases. Extremely large text inputs are rejected. Missing required fields, extra fields, wrong value types and violations of the calculation rules are input errors.

Alternative or Complementary methods

Use Roman Numeral Chord Analysis: Roman analysis preserves a chord root’s written degree and chromatic alteration. Enharmonic sounding equality can conceal different written functions. For a complementary task, use Tritone Substitution Pair Generator: A tritone-related dominant shares two guide-tone pitch classes with its counterpart. Enharmonic display is a separate naming choice.

References

Secondary Dominant Target Lookup — tool.io

Similar or alternative tools

Roman Numeral Chord Analysis
Roman analysis preserves a chord root’s written degree and chromatic alteration. Enharmonic sounding equality can conceal different written functions.
Tritone Substitution Pair Generator
A tritone-related dominant shares two guide-tone pitch classes with its counterpart. Enharmonic display is a separate naming choice.