Scatterplot matrix

Use a scatterplot matrix to look at every pair of several measures at once and to see which groups or relationships stand out.

Gentoo penguins are heavier, with longer flippers and shallower bills

Twelve penguins, every pair of four measurements

AdelieChinstrapGentoo

This chart cannot be displayed here: it needs JavaScript and WebGL.

each field has one range in every cell; the cells above the diagonal give the Pearson correlation of their two fields, computed by RichView

The same chart in each style

Source

Open in playground

Rich Markdown

```chart
type: splom
title: Gentoo penguins are heavier, with longer flippers and shallower bills
subtitle: Twelve penguins, every pair of four measurements
data:
  inline:
    - {species: Adelie, bill: 39, flipper: 181, mass: 3750, depth: 18.7}
    - {species: Adelie, bill: 40, flipper: 186, mass: 3800, depth: 18.0}
    - {species: Adelie, bill: 38, flipper: 190, mass: 3250, depth: 17.4}
    - {species: Adelie, bill: 36, flipper: 195, mass: 3450, depth: 19.3}
    - {species: Chinstrap, bill: 46, flipper: 192, mass: 3500, depth: 17.9}
    - {species: Chinstrap, bill: 50, flipper: 196, mass: 3900, depth: 19.5}
    - {species: Chinstrap, bill: 49, flipper: 193, mass: 3650, depth: 19.1}
    - {species: Chinstrap, bill: 51, flipper: 195, mass: 3750, depth: 18.7}
    - {species: Gentoo, bill: 46, flipper: 211, mass: 4500, depth: 13.7}
    - {species: Gentoo, bill: 48, flipper: 222, mass: 5400, depth: 14.3}
    - {species: Gentoo, bill: 50, flipper: 230, mass: 5700, depth: 15.2}
    - {species: Gentoo, bill: 47, flipper: 215, mass: 4750, depth: 14.5}
encoding:
  dimensions: [bill, flipper, mass, depth]
  color: species
```

Fields that matter

type: splom with encoding.dimensions listing two or more numeric columns; the grid has a row and a column for each
Below the diagonal each cell plots one point per row, with the column’s field across and the row’s field up
The diagonal names each field and gives its range; every cell of a field uses that range
Above the diagonal each cell gives the Pearson correlation of its two fields, computed by RichView and marked as derived in the readout
A scatterplot matrix takes at most six dimensions; above that the chart is not drawn and check raises chart.limit-exceeded naming the limit and the count
encoding.color colours the points by group and encoding.label names each row in its readout
A row with a missing value in any field is left out and reported; a value that is not a number is an error
Field names that do not fit their cell are left out and reported, so keep names short
encoding.facet makes one grid per value, all on the same ranges unless style.facet_scale is free

Interactions

Hover or focus a point to read the row’s values in that cell, or a diagonal or upper cell for the range or the correlation.
Click a legend entry to remove a group and back.
Open the Table view, Download PNG or CSV, or Expand the chart.