PieGlyph

PieGlyph is an R package aimed at replacing points in a plot with pie-charts glyphs, showing the relative proportions of different categories. The pie-chart glyphs are invariant to the axes and plot dimensions to prevent distortions when the plot dimensions are changed.

Installation

You can install the released version of PieGlyph from CRAN by running:

install.packages("PieGlyph")

Alternatively, you can install the development version of PieGlyph from GitHub with:

# install.packages("devtools")
devtools::install_github("rishvish/PieGlyph")

Example

Load libraries

library(tidyverse)
library(PieGlyph)

Simulate raw data

set.seed(123)
plot_data <- data.frame(response = rnorm(30, 100, 30),
                        system = 1:30,
                        group = sample(size = 30, x = c("G1", "G2", "G3"), replace = T),
                        A = round(runif(30, 3, 9), 2),
                        B = round(runif(30, 1, 5), 2),
                        C = round(runif(30, 3, 7), 2),
                        D = round(runif(30, 1, 9), 2))

Create plot

ggplot(data = plot_data, aes(x = system, y = response))+
  geom_pie_glyph(slices = c("A", "B", "C", "D"))+
  theme_minimal()

Alternative specification

The attributes can also be stacked into one column to generate the plot. This variant of the function is useful for situations when the data is in tidy format. See vignette('tidy-data') and vignette('pivot') for more information.

Stack the attributes in one column

plot_data_stacked <- plot_data %>%
  pivot_longer(cols = c("A", "B", "C", "D"), 
               names_to = "Attributes", 
               values_to = "values")
head(plot_data_stacked, 8)
#> # A tibble: 8 × 5
#>   response system group Attributes values
#>      <dbl>  <int> <chr> <chr>       <dbl>
#> 1     83.2      1 G1    A            5.8 
#> 2     83.2      1 G1    B            1.57
#> 3     83.2      1 G1    C            4.78
#> 4     83.2      1 G1    D            8.31
#> 5     93.1      2 G3    A            6.07
#> 6     93.1      2 G3    B            3.76
#> 7     93.1      2 G3    C            3.87
#> 8     93.1      2 G3    D            8.21

Create plot

ggplot(data = plot_data_stacked, aes(x = system, y = response))+
  # Along with slices column, values column is also needed now
  geom_pie_glyph(slices = 'Attributes', values = 'values')+
  theme_minimal()

Interactive pie-chart glyphs

It is also possible to create interactive pie-chart scatterplots using the geom_pie_interactive function via the ggiraph framework.

Hovering over a pie-chart glyph will show a tooltip containing information about the raw counts and percentages of the categories (system attributes in this example) shown in the pie-charts. All additional features by ggiraph are also supported. See the ggiraph book and vignette("interactive-pie-glyphs") for more information.

plot_obj <- ggplot(data = plot_data)+
              geom_pie_interactive(aes(x = system, y = response,
                                       data_id = system),
                                   slices = c("A", "B", "C", "D"), 
                                   colour = "black")+
              theme_classic()

girafe(ggobj = plot_obj, height_svg = 6, width_svg = 8)