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boxplot

lq.boxplot(..data, x=auto, whisker-pos=1.5, width=0.5, fill=none, stroke=1pt + black, median=1pt + orange, mean=none, whisker=auto, cap=auto, cap-length=0.25, outliers="o", outlier-size=5pt, outlier-fill=none, outlier-stroke=black, label=none, clip=true, z-index=2)

Computes and visualizes one or more boxplots from datasets.

In the following example, boxplots are generated for four different datasets. The default boxplot visualizes the first and third quartil as well as the median of the data with a box and shows traditional whiskers and outliers.

#lq.diagram(
  lq.boxplot(
    stroke: blue.darken(50%),
    (1, 2, 3, 4, 5, 6, 7, 8, 9, 21, 19),
    range(1, 30),
    (1, 28, 25, 30),
    (1, 2, 3, 4, 5, 6, 32),
  )
)

By default, the mean value is not shown but it can be visualized by setting the boxplot.mean parameter to a mark or line stroke.

#lq.diagram(
  lq.boxplot((1, 3, 10), mean: "."),
  lq.boxplot((1, 3, 10), mean: green, x: 2),
)

Boxplots can be richly customized as demonstrated below.

#lq.diagram(
  lq.boxplot(
    (1, 3, 10),
    stroke: luma(30%),
    fill: yellow,
    median: red
  ),
  lq.boxplot(
    (1.5, 3, 9),
    x: 2,
    whisker: blue,
    cap: red,
    cap-length: 0.7,
    median: green
  ),
  lq.boxplot(
    lq.linspace(5.3, 6.2) + (2, 3, 7, 9.5),
    x: 3,
    outliers: "x"
   ),
  lq.boxplot(
    lq.linspace(5.3, 6.2) + (2, 3, 7, 9.5),
    x: 4,
    outliers: none
  ),
)
Parameters

..data : array​

One or more data arrays to generate a boxplot from.

x : auto | int | float | array    default: auto​

The xx coordinate(s) to draw the boxplots at. If set to auto, boxplots will be created at integer positions starting with 1.

whisker-pos : int | float    default: 1.5​

The position of the whiskers. The length of the whiskers is at most whisker-pos * (q3 - q1) where q1 and q3 are the first and third quartils. However, the whiskers always end at an actual data point, so the length can be less then that. The default value of 1.5 is a very common convention established by John Tukey in Exploratory data analysis (1977).

width : int | float | array    default: 0.5​

The width of the boxplots in xx data coordinates. This can be a constant width applied to all boxplots or an array of widths matching the number of data sets.

fill : none | color | gradient | tiling    default: none​

How to fill the boxes.

stroke : length | color | stroke | gradient | tiling | dictionary    default: 1pt + black​

How to stroke the boxplot in general. Also see boxplot.whisker, boxplot.cap.

median : length | color | stroke | gradient | tiling | dictionary    default: 1pt + orange​

How to stroke the line that indicates the median of the data.

mean : none | lq.mark | str | stroke    default: none​

Whether and how to display the mean value. The mean value can be visualized with a mark (see plot.mark) or a line like the median.

whisker : auto | length | color | stroke | gradient | tiling | dictionary    default: auto​

How to stroke the whiskers. If set to auto, the stroke is inherited from boxplot.stroke.

cap : auto | length | color | stroke | gradient | tiling | dictionary    default: auto​

How to stroke the caps of the whiskers. If set to auto, the stroke is inherited from boxplot.stroke.

cap-length : int | float    default: 0.25​

The length of the whisker caps in xx data coordinates.

outliers : none | lq.mark | str    default: "o"​

Whether and how to display outliers. See plot.mark.

outlier-size : length    default: 5pt​

The size of the marks used to visualize outliers.

outlier-fill : none | auto | color    default: none​

How to fill outlier marks.

outlier-stroke : stroke    default: black​

How to stroke outlier marks.

label : content    default: none​

The legend label for this plot. See plot.label.

clip : bool    default: true​

Whether to clip the plot to the data area. See plot.clip.

z-index : int | float    default: 2​

Determines the zz position of this plot in the order of rendered diagram objects. See plot.z-index.