Sum brightness

"Modal Color Theory" (p. 6) describes two ways to measure the brightness of a scale. Sum brightness is the simpler of the two. It simply adds together the heights of all scale degrees above the tonic. See also Section 3.2 of "Bright notes, dark scales."

Usage

sum_brightness(set, mode = 0, edo = 12, rounder = 10)

Arguments

set

Numeric vector of pitch-classes in the set

mode

Which mode of the scale is desired? Integer, defaults to 0. Zero-indexed, so that the default is to return the sum brightness of the entered set.

edo

Number of unit steps in an octave. Defaults to 12.

rounder

Numeric (expected integer), defaults to 10: number of decimal places to round to when testing for equality.

Value

Single numeric value: the sum brightness of the specified mode.

Examples

c_major <- c(0, 2, 4, 5, 7, 9, 11)
d_major <- tn(c_major, 2, optic="p") # NB octave equivalent must NOT be used
c_dorian <- c(0, 2, 3, 5, 7, 9, 10)

sum_brightness(c_major)
#> [1] 38
sum_brightness(d_major)
#> [1] 38
sum_brightness(c_major, mode=1)
#> [1] 36
sum_brightness(c_dorian)
#> [1] 36