Hear a distribution, like a histogram — sonify

sonify_histogram() is the sound version of ggplot2::geom_histogram(). It sorts a column of numbers into bins, then sweeps across them from the lowest bin to the highest. Each bin is one note: the more rows in the bin, the higher (and louder) the note. Empty bins are silent.

Usage

sonify_histogram(
  data,
  x,
  weight = NULL,
  bins = NULL,
  binwidth = NULL,
  instrument = "piano",
  length = 20,
  bpm = NULL,
  log = FALSE,
  pan = FALSE,
  scale = "pentatonic",
  key = "C",
  range = NULL,
  engine = c("auto", "synth", "fluidsynth"),
  force = FALSE
)

Arguments

data: A data frame.
x: A column of numbers whose distribution you want to hear.
weight: Optional. A column of counts, for data that's already counted.
bins: Number of bins. Use bins or binwidth, not both. If you give neither, soundeR uses 30 bins and suggests picking a binwidth.
binwidth: How wide each bin is, in the units of x. Bins line up with multiples of binwidth, so binwidth = 10 for years gives 1900 to 1909, 1910 to 1919, and so on.
instrument: The instrument to use (see instruments()). With more than one voice, one instrument per voice, in order or named by voice. Voices you leave out play the piano.
length: Total length in seconds of the sweep.
bpm: Notes (bins) per minute. Use instead of length.
log: If TRUE, pitch follows the logarithm of the counts. That spreads out the notes when a few bins are much bigger than the rest.
pan: If TRUE, the sound travels from your left speaker to your right as the sweep moves from the lowest bin to the highest, so you can hear where you are along the axis.
scale: The musical scale that pitches snap to. See sound_scales(). The default, "pentatonic", sounds pleasant with any data. "happy" is another name for it, and "sad" switches to a minor pentatonic. With "none", the built-in synth plays exact frequencies, but real instruments play the nearest semitone.
key: The key of the scale, like "C", "G" or "Bb".
range: The lowest and highest notes to use, like c("C3", "C6"). By default, the usual range of the instrument (see instruments()), or the range several instruments share. Built-in sounds use C3 to C6.
engine: How to make the sound. "auto" uses real instruments when the fluidsynth package and a soundfont are available, and the built-in synth otherwise. See sound_setup().
force: Set to TRUE to allow sonifications longer than 20 minutes.

Value

A sonification object. Print it to hear it, or pass it to sonify_video() to see it as a histogram.

Details

Like a histogram, what you hear depends on the bins. Try a few values of binwidth: narrow bins show detail (and noise), wide bins show the overall shape.

If your data is already counted, with one row per value and a column of counts, give that column to weight.

notes() on the result has one row per non-empty bin: bin_start and bin_end give its edges (each bin includes its start but not its end), value is its count, and row is the bin's number, counting from the lowest.

Examples

# Already-counted data: houses built in Nebraska, by year
ne_house_years
#> # A tibble: 182 × 2
#>    year_built houses
#>         <int>  <int>
#>  1       1800      4
#>  2       1820      1
#>  3       1821      1
#>  4       1840      2
#>  5       1848      1
#>  6       1849      2
#>  7       1850     10
#>  8       1851      1
#>  9       1853      1
#> 10       1854      3
#> # ℹ 172 more rows

# One bin per decade
ne_house_years |>
  sonify_histogram(year_built, weight = houses, binwidth = 10, instrument = "marimba")
21 notes · 20.0 seconds · marimba

# Raw values work too
sonify_histogram(data.frame(x = rnorm(500)), x, bins = 20, instrument = "bell")
20 notes · 20.0 seconds · bell