Hear a distribution as a smooth curve — sonify

sonify_density() is the sound version of ggplot2::geom_density(). It draws a smooth curve through the distribution of a column, then sweeps across it from the lowest value to the highest. By default you hear one continuous tone that glides up where the data is dense and down where it's sparse, and gets quieter where there's little data.

Usage

sonify_density(
  data,
  x,
  weight = NULL,
  adjust = 1,
  glide = TRUE,
  instrument = if (glide) "triangle" else "piano",
  length = 10,
  points = 120,
  scale = "pentatonic",
  key = "C",
  range = NULL,
  pan = FALSE,
  engine = c("auto", "synth", "fluidsynth")
)

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.
adjust: Make the curve smoother (bigger) or more detailed (smaller). 2 is twice as smooth as the default.
glide: If TRUE (the default), one continuous gliding tone. If FALSE, a run of notes, which works with any instrument.
instrument: The sound to use. With glide = TRUE, "sine", "triangle" or "square".
length: Total length in seconds of the sweep.
points: How many points along the curve to use.
scale: The musical scale notes snap to when glide = FALSE. See sound_scales(). The glide always follows the curve exactly.
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.
pan: If TRUE, the sound travels from your left speaker to your right as the sweep moves across the curve.
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().

Value

A sonification object. Print it to hear it, or pass it to sonify_video() to see the curve.

Details

adjust controls how smooth the curve is, just like in geom_density(): bigger values smooth more, smaller values show more detail.

The glide uses soundeR's built-in sounds ("sine", "triangle" or "square"), because real instruments play separate notes. With glide = FALSE, the curve is played as a quick run of notes instead, and any instrument works.

notes() on the result has one row per point along the curve: x_value is where the point sits, value is the curve's height there.

Examples

sonify_density(data.frame(x = c(rnorm(300), rnorm(100, 4))), x)
120 notes · 10.0 seconds · triangle

# Already-counted data
ne_house_years |>
  sonify_density(year_built, weight = houses, adjust = 4)
120 notes · 10.0 seconds · triangle