Trends API chord input

product questions
1

I’ve started exploring the Trends API, and while this page explains the basics of how to navigate it, it only describes how to input the basic major diatonic chords. After some trial and error, I found these others:

Major
I     ii     iii     IV    V    VI    vii
1    2     3     4      5     6     7

Minor
i      iiº     bIII    iv    v      bVI   bVII
B1   B2   B3    B4   B5   B6    B7

Dorian
i      ii     bIII    IV      v     viº    bVII
D1  D2   D3    D4    D5   D6   D7

Phrygian
i      bII     bIII   iv     vº     bVI   bvii
Y1   Y2    Y3    Y4   Y5    Y6    Y7

Lydian
I      II      iii     #ivº   V     vi     vii
L1   L2    L3    L4    L5    L6   L7

Mixolydian
I      ii      iiiº     IV     v      vi      bVII
M1  M2   M3   M4    M5   M6   M7

Locrian
iº     bII     biii    iv     bV    bVI    bvii
C1   C2    C3    C4   C5    C6    C7

Inversions
6    64    65    43    42

Embellishments
7    add9 sus4 sus2 7sus4 7sus2 sus42
7    (I assume none of these inputs exist)

Applied
V/    IV/    vii/
5/    4/    7/

Redundant: (will return a “No songs match this chord progression” message)
D1: Dorian i = Minor i
L2 and 4/6: II = IV/vi = V/V
D7, M7 and 4/4: Dorian bVII = Mixolydian bVII = IV/IV = Minor bVII
5/1 and 4/1: V/I and IV/I = V and IV, respectively
5/4 returns no results, but 57/4 does: V/IV = I, except when dominant
7/1: viiº/I = viiº

  1. Did I miss anything?
  2. Is it possible to input supermodal chords? If so, how?
1 Like
2

I made a more formal metasyntax for this a while ago.

About the “redundant” chords; Some of these chords used to have entries in the database, but I removed them manually from time to time to ensure that the database is clean and contains as few duplicate chords as possible, before the API receives an overhaul. Some chords are nonetheless different from others due to the possibility of embellishments (e.g. L3 is different from 3 because their add9 chords yield Em(add9) and Em(addb9) respectively).

Magic Chord sometimes gives S(3)3 instead of 5/6; this seems to be the proper way of addressing supermodal chords, but they are already rejected by the API and analyses containing any supermodal chord will not be found in the Trends page. Major V in Minor is the only supermodal chord accepted right now.

EDIT: It seems that all results of 4/4 are absorbed into b7 automatically, as does L2; this applies only to the root position, not 46/4 or 464/4 (or other inversions). If I remember correctly, this happens to all applied dominants and IV/IV, but the API document does not clearly indicate when such assimilation occurs.

3

Hello everyone,
I’ve started to explore the trends API also, when using
https://api.hooktheory.com/v1/trends/nodes

It shows only till chord_ID 77. Is there a way to see other pages?