Skip to contents

Pie Chart

Source: R/piechart.R
PieChart.Rd

Pie chart to illustrate numerical proportion of each group.

Usage

PieChart(
  data,
  x,
  y = NULL,
  label = y,
  split_by = NULL,
  split_by_sep = "_",
  clockwise = TRUE,
  facet_by = NULL,
  facet_scales = "free_y",
  facet_ncol = NULL,
  facet_nrow = NULL,
  facet_byrow = TRUE,
  theme = "theme_this",
  theme_args = list(),
  palette = "Paired",
  palcolor = NULL,
  alpha = 1,
  aspect.ratio = 1,
  legend.position = "right",
  legend.direction = "vertical",
  title = NULL,
  subtitle = NULL,
  xlab = NULL,
  ylab = NULL,
  keep_empty = FALSE,
  combine = TRUE,
  nrow = NULL,
  ncol = NULL,
  byrow = TRUE,
  seed = 8525,
  axes = NULL,
  axis_titles = axes,
  guides = NULL,
  design = NULL,
  ...
)

Arguments

data

A data frame.

x

A character string specifying the column name of the data frame to plot for the x-axis.

y

A character string of the column name to plot on the y-axis. A numeric column is expected. If NULL, the count of each x column will be used.

label

Which column to use as the label. NULL means no label. Default is the same as y. If y is NULL, you should use ".y" to specify the count as the label. If TRUE, the y values will be used as the label.

split_by

The column(s) to split data by and plot separately.

split_by_sep

The separator for multiple split_by columns. See split_by

clockwise

A logical value to draw the pie chart clockwise or not.

facet_by

A character string specifying the column name of the data frame to facet the plot. Otherwise, the data will be split by split_by and generate multiple plots and combine them into one using patchwork::wrap_plots

facet_scales

Whether to scale the axes of facets. Default is "fixed" Other options are "free", "free_x", "free_y". See ggplot2::facet_wrap

facet_ncol

A numeric value specifying the number of columns in the facet. When facet_by is a single column and facet_wrap is used.

facet_nrow

A numeric value specifying the number of rows in the facet. When facet_by is a single column and facet_wrap is used.

facet_byrow

A logical value indicating whether to fill the plots by row. Default is TRUE.

theme

A character string or a theme class (i.e. ggplot2::theme_classic) specifying the theme to use. Default is "theme_this".

theme_args

A list of arguments to pass to the theme function.

palette

A character string specifying the palette to use. A named list or vector can be used to specify the palettes for different split_by values.

palcolor

A character string specifying the color to use in the palette. A named list can be used to specify the colors for different split_by values. If some values are missing, the values from the palette will be used (palcolor will be NULL for those values).

alpha

A numeric value specifying the transparency of the plot.

aspect.ratio

A numeric value specifying the aspect ratio of the plot.

legend.position

A character string specifying the position of the legend. if waiver(), for single groups, the legend will be "none", otherwise "right".

legend.direction

A character string specifying the direction of the legend.

title

A character string specifying the title of the plot. A function can be used to generate the title based on the default title. This is useful when split_by is used and the title needs to be dynamic.

subtitle

A character string specifying the subtitle of the plot.

xlab

A character string specifying the x-axis label.

ylab

A character string specifying the y-axis label.

keep_empty

Logical or character. Whether to keep unused factor levels on categorical axes.

  • FALSE (default): Drop unused factor levels via droplevels().

  • TRUE: Keep all factor levels defined in the data, even if they have no observations. For plots with both x and y categorical, applies to both axes.

  • "x": Keep unused levels only on the x-axis, drop from y-axis.

  • "y": Keep unused levels only on the y-axis, drop from x-axis.

  • c("x", "y") or "xy": Explicitly keep unused levels on both axes (same as TRUE).

Note: This parameter is distinct from keep_na. Use keep_empty = TRUE when you need to show all possible categories (e.g., all 12 months even if some have no data). For more complex completeness requirements, use tidyr::complete() before plotting.

Backward compatibility: If keep_na is not specified and keep_empty is provided, keep_empty will control both NA values and unused levels (legacy behavior).

combine

Whether to combine the plots into one when facet is FALSE. Default is TRUE.

nrow

A numeric value specifying the number of rows in the facet.

ncol

A numeric value specifying the number of columns in the facet.

byrow

A logical value indicating whether to fill the plots by row.

seed

The random seed to use. Default is 8525.

axes

A string specifying how axes should be treated. Passed to patchwork::wrap_plots(). Only relevant when split_by is used and combine is TRUE. Options are:

  • 'keep' will retain all axes in individual plots.

  • 'collect' will remove duplicated axes when placed in the same run of rows or columns of the layout.

  • 'collect_x' and 'collect_y' will remove duplicated x-axes in the columns or duplicated y-axes in the rows respectively.

axis_titles

A string specifying how axis titltes should be treated. Passed to patchwork::wrap_plots(). Only relevant when split_by is used and combine is TRUE. Options are:

  • 'keep' will retain all axis titles in individual plots.

  • 'collect' will remove duplicated titles in one direction and merge titles in the opposite direction.

  • 'collect_x' and 'collect_y' control this for x-axis titles and y-axis titles respectively.

guides

A string specifying how guides should be treated in the layout. Passed to patchwork::wrap_plots(). Only relevant when split_by is used and combine is TRUE. Options are:

  • 'collect' will collect guides below to the given nesting level, removing duplicates.

  • 'keep' will stop collection at this level and let guides be placed alongside their plot.

  • 'auto' will allow guides to be collected if a upper level tries, but place them alongside the plot if not.

design

Specification of the location of areas in the layout, passed to patchwork::wrap_plots(). Only relevant when split_by is used and combine is TRUE. When specified, nrow, ncol, and byrow are ignored. See patchwork::wrap_plots() for more details.

...

Additional arguments.

Value

A ggplot object or wrap_plots object or a list of ggplot objects

Examples

data <- data.frame(
   x = c("A", "B", "C", "D", "E", "F", "G", "H"),
   y = c(10, 8, 16, 4, 6, 12, 14, 2),
   group = c("G1", "G1", "G2", "G2", "G3", "G3", "G4", "G4"),
   facet = c("F1", "F2", "F3", "F4", "F1", "F2", "F3", "F4")
)

PieChart(data, x = "x", y = "y")

PieChart(data, x = "x", y = "y", clockwise = FALSE)

PieChart(data, x = "x", y = "y", label = "group")

PieChart(data, x = "x", y = "y", facet_by = "facet")

PieChart(data, x = "x", y = "y", split_by = "group")

PieChart(data, x = "x", y = "y", split_by = "group",
         palette = list(G1 = "Reds", G2 = "Blues", G3 = "Greens", G4 = "Purp"))


# y from count
PieChart(data, x = "group")

# add label
PieChart(data, x = "group", label = ".y")