Some composers speak of "interval vector music". I picked up the lingo somewhere. Theorists felt the words were not apt, and I did not disagree.
I try to explain the problems here.
No doubt, the word "vector" implies forces that can be measured. We used the term figuratively in our musical discussions.
Jeff Nichols has a passage in his trio for theorbo, recorder and viola where semiones gradually disappear. We thought of that as an interval vector characterized by a preponderance of semintones transitioning to a lack of semitones. It works. The passage has a direction, but there are so many ways that this can be done. The various routes involve much other intervalic fallout. Adding or subtracting an interval can be done in many ways, and additional intervals appear or disappear depending upon the route.
Here is the opening of the Beatles song, Mother Nature's Son:
The song begins with hippie earnestness:
D: Born a G/D: poor young country D: boy
Bm: Mother D/A: nature's vii7: son, elides to E7
The earnestness disappears in a snap when the low E is introduced. The song moves abruptly from hippie to skiffle.
The *interval vector* abruptly shifts from minor third preponderance to major second preponderance. (For the moment, think that the B is still in play.) The tritone is abruptly reinterpreted from the 3 cycle to the 2 cycle. G#-B-D is displaced by D-E-F#-G#. The reiorientation is hilarious, and the Beatles are not unaware of the humor.
I steal this in a number of places. It is in my arsenal. I theorized: the M5 of the move will be equally powerful. I tried it in my treatment of the traditional Quebecois folksong, Ziguezon.
Where the Gb appears, that is the M5 equivalent of adding the E in the Beatles move. In both cases, the added note breaks the octotonic.
And you see the Beatles move where the D appears in measure 110. The M5 version of the move happens mid-phrase, and the Beatles version happens at the end.
The Beatles move happens at the end of every verse.
Every interval vector shift is unique, and so the use of "vector" is always misleading.