ggpairs plot with custom colours — ggpairs

Creates a ggpairs plot (see GGally::ggpairs()) where the colours and shapes can differ between the upper triangle, lower triangle and diagonal plots.

Usage

ggpairs_custom(
  toplot,
  vars,
  colour_upper = NULL,
  colour_diag = colour_upper,
  colour_lower = colour_upper,
  shape_upper = NULL,
  shape_lower = shape_upper,
  scale_colour_upper = NULL,
  scale_colour_diag = NULL,
  scale_colour_lower = NULL,
  scale_shape_upper = NULL,
  scale_shape_lower = NULL,
  title = NULL,
  point_size = 1.5
)

Arguments

toplot: Tibble in wide format, with observations as rows and variables as columns.
vars: Character vector, names of the columns in toplot that correspond to variables to be used for the plot matrix.
colour_upper: Character, name of column in toplot to use for colouring observations in the upper triangle plots. Default value is NULL.
colour_diag: Character, name of column in toplot to use for colouring observations in the diagonal plots. By default, will follow colour_upper.
colour_lower: Character, name of column in toplot to use for colouring observations in the lower triangle plots. By default, will follow colour_upper.
shape_upper: Character, name of column in toplot to use for shaping observations in the upper triangle plots. Default value is NULL.
shape_lower: Character, name of column in toplot to use for shaping observations in the lower triangle plots. By default, will follow shape_upper.
scale_colour_upper: ggplot2 colour scale to use for the upper triangle plots. Default value is NULL (if colour_upper is not NULL, will use ggplot2 default colour scales).
scale_colour_diag: ggplot2 colour scale to use for the diagonal plots. If NULL (default), the colour scale used for the upper triangle plots will be used if colour_diag is equal to colour_upper; or the colour scale used for the lower triangle plots will be used if colour_diag is equal to colour_lower.
scale_colour_lower: ggplot2 colour scale to use for the lower triangle plots. If NULL (default), the colour scale used for the upper triangle plots will be used.
scale_shape_upper: ggplot2 shape scale to use for the upper triangle plots. Default value is NULL (if shape_upper is not NULL, will use ggplot2 default shape scale).
scale_shape_lower: ggplot2 shape scale to use for the lower triangle plots. If NULL (default), the shape scale used for the upper triangle plots will be used.
title: Character, title of the plot. Default value is NULL (no title added to the plot).
point_size: Numeric, the size of points (in pt) in the plot. Default value is 1.5.

Value

A ggmatrix plot.

Examples

if (FALSE) { # \dontrun{
library(palmerpenguins)
library(ggplot2)
data("penguins")

vars <- c(
  "bill_length_mm",
  "bill_depth_mm",
  "flipper_length_mm"
)

toplot <- penguins |>
  dplyr::filter(!is.na(bill_length_mm))

# simple scatterplots of the variables
ggpairs_custom(toplot, vars)

# colouring points by species, using custom colour palette
ggpairs_custom(
  toplot,
  vars,
  colour_upper = "species",
  scale_colour_upper = scale_colour_brewer(palette = "Set1")
)

# now adding the sex variable as shape of the points
ggpairs_custom(
  toplot,
  vars,
  colour_upper = "species",
  scale_colour_upper = scale_colour_brewer(palette = "Set1"),
  shape_upper = "sex"
)

# using the lower plots to show the island as colour
ggpairs_custom(
  toplot,
  vars,
  colour_upper = "species",
  scale_colour_upper = scale_colour_brewer(palette = "Set1"),
  shape_upper = "sex",
  colour_lower = "island",
  scale_colour_lower = scale_colour_viridis_d()
)

# showing species and sex in upper plots, body mass and island
# in lower plots
ggpairs_custom(
  toplot,
  vars,
  colour_upper = "species",
  scale_colour_upper = scale_colour_brewer(palette = "Set1"),
  shape_upper = "sex",
  shape_lower = "island",
  colour_lower = "body_mass_g",
  scale_colour_lower = scale_colour_viridis_c(option = "plasma")
)

# same as above, but the diagonal plots show density per year
ggpairs_custom(
  toplot,
  vars,
  colour_upper = "species",
  scale_colour_upper = scale_colour_brewer(palette = "Set1"),
  shape_upper = "sex",
  shape_lower = "island",
  colour_lower = "body_mass_g",
  scale_colour_lower = scale_colour_viridis_c(option = "plasma"),
  colour_diag = "year"
)

# common legend if the diagonal follows the colour of the lower plots
ggpairs_custom(
  toplot,
  vars,
  colour_upper = "species",
  scale_colour_upper = scale_colour_brewer(palette = "Set1"),
  colour_lower = "island",
  scale_colour_lower = scale_colour_brewer(palette = "Accent"),
  colour_diag = "island"
)
} # }