The Best GGPlot Themes You Should Know

13 Nov

GGPlot Themes Gallery

Alboukadel

GGPLOT2 Graphical Parameters

ggplot2

1 1

In this R graphics tutorial, we present a gallery of ggplot themes.

You’ll learn how to:

Change the default ggplot theme by using the list of the standard themes available in ggplot2 R package. Our selection of best ggplot themes for professional publications or presentations, include: theme_classic(), theme_minimal() and theme_bw(). Another famous theme is the dark theme: theme_dark().
Use other helpful examples of ggplot2 themes available in the ggthemes R package. These include theme_tufte(), theme_economist() and theme_hc(). You’ll also see how to create a tufte minimalist boxplot.
Modify, at once, all the theme text elements by specifying the ggplot base_size argument in the theme functions. Example: p + theme_minimal(base_size = 18).
Change the theme for the entire session using theme_set(). For example, is you type theme_set(theme_classic(base_size = 16)) in the R console, then the classic theme will be automatically applied to every plot you draw. The theme_set() function completely override the current active theme.
Create your own custom theme.

Contents:

Basic ggplot
Change themes
Override the current theme: theme_set
Change ggplot theme base_size and base_family
Create a custom theme
Conclusion

Basic ggplot

Data: ToothGrowth

# Convert the column dose to factor variable
data("ToothGrowth")
ToothGrowth$dose <- as.factor(ToothGrowth$dose)

# Create a simple boxplot
library(ggplot2)
p <- ggplot(ToothGrowth, aes(x = dose, y = len)) + 
  geom_boxplot()

Change themes

Use themes in ggplot2

Several simple functions are available in ggplot2 package to set easily a ggplot theme. These include:

theme_gray(): Gray background color and white grid lines. Put the data forward to make comparisons easy.
theme_bw(): White background and gray grid lines. May work better for presentations displayed with a projector.
theme_linedraw(): A theme with black lines of various widths on white backgrounds, reminiscent of a line drawings.
theme_light(): A theme similar to theme_linedraw() but with light grey lines and axes, to direct more attention towards the data.

p + theme_gray(base_size = 14) 

p + theme_bw()

p + theme_linedraw()

p + theme_light()

theme_dark(): Same as theme_light but with a dark background. Useful to make thin coloured lines pop out.
theme_minimal(): A minimal theme with no background annotations
theme_classic(): A classic theme, with x and y axis lines and no gridlines.
theme_void(): a completely empty theme, useful for plots with non-standard coordinates or for drawings.

p + theme_dark() 

p + theme_minimal()

p + theme_classic()

p + theme_void()

Use ggthemes

The R package ggthemes provides another gallery of custom ggplot themes, which include:

theme_tufte(): a minimalist theme
theme_economist(): theme based on the plots in the economist magazine
theme_stata(): theme based on stata graph schemes.
theme_hc(): theme based on Highcharts JS

To use these themes, first install and load the ggthemes package as follow :

install.packages("ggthemes") # Install 

library(ggthemes) # Load

Then, create two basic ggplot: scatter plot and boxplot.

# Scatter plot
sp <- ggplot(mtcars, aes(wt, mpg)) +
  geom_point() 
sp

# Boxblot
ToothGrowth$dose <- as.factor(ToothGrowth$dose)
bxp <- ggplot(ToothGrowth, aes(x = dose, y = len)) +
  geom_boxplot(aes(fill = dose))
bxp

theme_tufte

Key R functions:

theme_tufte(): set tufte theme
geom_tufteboxplot(): Create tufte boxplot
geom_rangeframe(): Extend axis lines to the maximum and the minimum of the plot data

Create a scatter plot with tufte theme:

library(ggthemes)
sp + geom_rangeframe() +  theme_tufte()

Create a tufte boxplot. The function `geom_tufteboxplot() creates several variants of Tufte’s minimal-ink boxplots. The following R code, will create two types of boxplots.

Boxplot 1:
- a point indicates the median,
- a gap indicates the interquartile range,
- and lines the whiskers
Boxplot 2:
- a wide line indicates interquartile range,
- a gap indicates the median,
- and lines indicate the minimum and maximum

p <- ggplot(ToothGrowth, aes(factor(dose), len)) +
  theme_tufte(ticks = FALSE)

# Box plot 1
p + geom_tufteboxplot()

# Box plot 2
p + geom_tufteboxplot(median.type = "line", 
                      whisker.type = 'line',
                      hoffset = 0, width = 3)

theme_economist

Key R functions:

theme_economist()
scale_fill_economist()
scale_color_economist()

Create a boxplot with the economist theme:

bxp + theme_economist() + scale_fill_economist()

theme_stata

Key R functions:

theme_stata()
scale_fill_stata()
scale_color_stata()

bxp + theme_stata() + scale_fill_stata()

theme_hc

bxp + theme_hc()+ scale_colour_hc()

Override the current theme: theme_set

The function theme_set() can be used to change the theme for the entire session. It returns the old theme, so that we can restore it later.

p <- ggplot(ToothGrowth, aes(x = dose, y = len)) + 
  geom_boxplot()
# Set theme_bw()
old.theme <- theme_set(theme_bw())
p

# Restore the old theme
theme_set(old.theme)
p

Change ggplot theme base_size and base_family

Note that, the theme functions can take the two arguments below :

base_size: base font size (to change the size of all plot text elements)
base_family: base font family

For example, the size of all the plot text elements can be easily changed at once, using:

p + theme_gray(base_size = 18, base_family = "Times")

Create a custom theme

The function theme() is used to control non-data parts of a ggplot2 graph, including

Line elements: axis lines, minor and major grid lines, plot panel border, axis ticks background color, etc.
Text elements: plot title, axis titles, legend title and text, axis tick mark labels, etc.
Rectangle elements: plot background, panel background, legend background, etc.

There is a specific function to modify each of these three elements :

element_line(color, size, linetype) to modify the line elements of the theme
element_text(face, color, size, hjust, vjust, angle) to modify the text elements
element_rect(fill, color, size, linetype) to modify the rectangle elements

Note that, each of the theme elements can be removed using the function element_blank().

The easiest way to create a custom theme is, for example, to extract and modify the R code of the function theme_gray() or any other theme functions [theme_bw(), theme_classic(), etc].

Build your theme from scrach by starting with the source code of the function theme_gray():

theme_gray

function (base_size = 11, base_family = "") {
  
 half_line <- base_size/2
 
theme(
  ...
  axis.text = element_text(size = rel(0.8), colour = "grey30"),
  ...
  )

}

Create a new theme called theme_bluewhite() by starting with the source code of the function theme_bw(). We’ll replace only some theme elements.

# Create a new theme
theme_bluewhite <- function (base_size = 11, base_family = "") {
    theme_bw() %+replace% 
    theme(
      panel.grid.major  = element_line(color = "white"),
      panel.background = element_rect(fill = "lightblue"),
      panel.border = element_rect(color = "lightblue", fill = NA),
      axis.line = element_line(color = "lightblue"),
      axis.ticks = element_line(color = "lightblue"),
      axis.text = element_text(color = "steelblue")
      )
}

# Using our new theme
ggplot(ToothGrowth, aes(dose, len)) +
  geom_boxplot() +
  theme_bluewhite()

Conclusion

We present a list of ggplot themes to easily customize your graphs. We also describe how to create a custom ggplot theme.

The main points as shown below.

Create an example of ggplot:

library(ggplot2)
p <- ggplot(ToothGrowth, aes(x = dose, y = len)) + 
  geom_boxplot()

Change ggplot the background theme by using one of the following professional themes:
- theme_bw(), theme_minimal(), theme_classic() and theme_dark() [in ggplot2 package]
- theme_tufte() and theme_economist() [in ggthemes]