tabr (version 0.3.5)

note_slice: Slice, rotate, shift and arpeggiate notes

Description

Helper functions for indexing and moving notes within noteworthy strings.

Usage

note_slice(notes, ...)
note_rotate(notes, n = 0)
note_shift(notes, n = 0)
note_arpeggiate(notes, n = 0, ...)

Arguments

notes

character, a noteworthy string, space-delimited or vector of individual entries.

...

For note_slice, an integer or logical vector. See details. For note_arpeggiate, additional arguments to transpose, specifically key and style.

n

integer, degree of rotation.

Value

character

Details

note_slice subsets the timesteps of a noteworthy string by integer index or logical vector of length equal to the number of timesteps.

note_rotate simply rotates anything space-delimited or vectorized in place. It allows chords. Octave numbering is ignored if present.

For note_shift the entire sequence is shifted up or down, as if inverting a broken chord. In this case notes is strictly interpreted and may not include chords. Octave numbering applies, though large multi-octave gaps will be condensed in the process. Given the context of note_shift, the notes sequence should be ordered by increasing pitch. If it is not, ordering will be forced with each inversion during the n shifts.

note_arpeggiate also allows notes only. It is similar to note_shift, except that instead of a moving window, it grows from the original set of notes by n in the direction of the sign of n.

Examples

# NOT RUN {
x <- "e_2 a_, c#f#a#"
note_slice(x, 2:3)
note_slice(x, c(FALSE, TRUE, TRUE))

note_rotate(x, 1)

note_shift("c e g", 1)
note_shift("c e g", -4)

note_arpeggiate("c e g", 5)
note_arpeggiate("c e g", -5)
# }