ggplot2 (version 2.2.0)

theme: Modify components of a theme

Description

Use theme() to modify individual components of a theme, allowing you to control the appearance of all non-data components of the plot. theme() only affects a single plot: see theme_update if you want modify the active theme, to affect all subsequent plots.

Usage

theme(line, rect, text, title, aspect.ratio, axis.title, axis.title.x, axis.title.x.top, axis.title.y, axis.title.y.right, axis.text, axis.text.x, axis.text.x.top, axis.text.y, axis.text.y.right, axis.ticks, axis.ticks.x, axis.ticks.y, axis.ticks.length, axis.line, axis.line.x, axis.line.y, legend.background, legend.margin, legend.spacing, legend.spacing.x, legend.spacing.y, legend.key, legend.key.size, legend.key.height, legend.key.width, legend.text, legend.text.align, legend.title, legend.title.align, legend.position, legend.direction, legend.justification, legend.box, legend.box.just, legend.box.margin, legend.box.background, legend.box.spacing, panel.background, panel.border, panel.spacing, panel.spacing.x, panel.spacing.y, panel.grid, panel.grid.major, panel.grid.minor, panel.grid.major.x, panel.grid.major.y, panel.grid.minor.x, panel.grid.minor.y, panel.ontop, plot.background, plot.title, plot.subtitle, plot.caption, plot.margin, strip.background, strip.placement, strip.text, strip.text.x, strip.text.y, strip.switch.pad.grid, strip.switch.pad.wrap, ..., complete = FALSE, validate = TRUE)

Arguments

line
all line elements (element_line)
rect
all rectangular elements (element_rect)
text
all text elements (element_text)
title
all title elements: plot, axes, legends (element_text; inherits from text)
aspect.ratio
aspect ratio of the panel
axis.title
label of axes (element_text; inherits from text)
axis.title.x
x axis label (element_text; inherits from axis.title)
axis.title.x.top
x axis label on top axis (element_text; inherits from axis.title.x)
axis.title.y
y axis label (element_text; inherits from axis.title)
axis.title.y.right
y axis label on right axis (element_text; inherits from axis.title.y)
axis.text
tick labels along axes (element_text; inherits from text)
axis.text.x
x axis tick labels (element_text; inherits from axis.text)
axis.text.x.top
x axis tick labels on top axis (element_text; inherits from axis.text.x)
axis.text.y
y axis tick labels (element_text; inherits from axis.text)
axis.text.y.right
y axis tick labels on right axis (element_text; inherits from axis.text.y)
axis.ticks
tick marks along axes (element_line; inherits from line)
axis.ticks.x
x axis tick marks (element_line; inherits from axis.ticks)
axis.ticks.y
y axis tick marks (element_line; inherits from axis.ticks)
axis.ticks.length
length of tick marks (unit)
axis.line
lines along axes (element_line; inherits from line)
axis.line.x
line along x axis (element_line; inherits from axis.line)
axis.line.y
line along y axis (element_line; inherits from axis.line)
legend.background
background of legend (element_rect; inherits from rect)
legend.margin
the margin around each legend (margin)
legend.spacing
the spacing between legends (unit)
legend.spacing.x
the horizontal spacing between legends (unit); inherits from legend.spacing
legend.spacing.y
the horizontal spacing between legends (unit); inherits from legend.spacing
legend.key
background underneath legend keys (element_rect; inherits from rect)
legend.key.size
size of legend keys (unit)
legend.key.height
key background height (unit; inherits from legend.key.size)
legend.key.width
key background width (unit; inherits from legend.key.size)
legend.text
legend item labels (element_text; inherits from text)
legend.text.align
alignment of legend labels (number from 0 (left) to 1 (right))
legend.title
title of legend (element_text; inherits from title)
legend.title.align
alignment of legend title (number from 0 (left) to 1 (right))
legend.position
the position of legends ("none", "left", "right", "bottom", "top", or two-element numeric vector)
legend.direction
layout of items in legends ("horizontal" or "vertical")
legend.justification
anchor point for positioning legend inside plot ("center" or two-element numeric vector) or the justification according to the plot area when positioned outside the plot
legend.box
arrangement of multiple legends ("horizontal" or "vertical")
legend.box.just
justification of each legend within the overall bounding box, when there are multiple legends ("top", "bottom", "left", or "right")
legend.box.margin
margins around the full legend area, as specified using margin
legend.box.background
background of legend area (element_rect; inherits from rect)
legend.box.spacing
The spacing between the plotting area and the legend box (unit)
panel.background
background of plotting area, drawn underneath plot (element_rect; inherits from rect)
panel.border
border around plotting area, drawn on top of plot so that it covers tick marks and grid lines. This should be used with fill=NA (element_rect; inherits from rect)
panel.spacing
spacing between facet panels (unit)
panel.spacing.x
horizontal spacing between facet panels (unit; inherits from panel.spacing)
panel.spacing.y
vertical spacing between facet panels (unit; inherits from panel.spacing)
panel.grid
grid lines (element_line; inherits from line)
panel.grid.major
major grid lines (element_line; inherits from panel.grid)
panel.grid.minor
minor grid lines (element_line; inherits from panel.grid)
panel.grid.major.x
vertical major grid lines (element_line; inherits from panel.grid.major)
panel.grid.major.y
horizontal major grid lines (element_line; inherits from panel.grid.major)
panel.grid.minor.x
vertical minor grid lines (element_line; inherits from panel.grid.minor)
panel.grid.minor.y
horizontal minor grid lines (element_line; inherits from panel.grid.minor)
panel.ontop
option to place the panel (background, gridlines) over the data layers. Usually used with a transparent or blank panel.background. (logical)
plot.background
background of the entire plot (element_rect; inherits from rect)
plot.title
plot title (text appearance) (element_text; inherits from title) left-aligned by default
plot.subtitle
plot subtitle (text appearance) (element_text; inherits from title) left-aligned by default
plot.caption
caption below the plot (text appearance) (element_text; inherits from title) right-aligned by default
plot.margin
margin around entire plot (unit with the sizes of the top, right, bottom, and left margins)
strip.background
background of facet labels (element_rect; inherits from rect)
strip.placement
placement of strip with respect to axes, either "inside" or "outside". Only important when axes and strips are on the same side of the plot.
strip.text
facet labels (element_text; inherits from text)
strip.text.x
facet labels along horizontal direction (element_text; inherits from strip.text)
strip.text.y
facet labels along vertical direction (element_text; inherits from strip.text)
strip.switch.pad.grid
space between strips and axes when strips are switched (unit)
strip.switch.pad.wrap
space between strips and axes when strips are switched (unit)
...
additional element specifications not part of base ggplot2. If supplied validate needs to be set to FALSE.
complete
set this to TRUE if this is a complete theme, such as the one returned by theme_grey(). Complete themes behave differently when added to a ggplot object. Also, when setting complete = TRUE all elements will be set to inherit from blank elements.
validate
TRUE to run validate_element, FALSE to bypass checks.

Theme inheritance

Theme elements inherit properties from other theme elements. For example, axis.title.x inherits from axis.title, which in turn inherits from text. All text elements inherit directly or indirectly from text; all lines inherit from line, and all rectangular objects inherit from rect. This means that you can modify the appearance of multiple elements by setting a single high-level component.

See Also

+.gg and %+replace%, element_blank, element_line, element_rect, and element_text for details of the specific theme elements.

Examples

Run this code
p1 <- ggplot(mtcars, aes(wt, mpg)) +
  geom_point() +
  labs(title = "Fuel economy declines as weight increases")
p1

# Plot ---------------------------------------------------------------------
p1 + theme(plot.title = element_text(size = rel(2)))
p1 + theme(plot.background = element_rect(fill = "green"))

# Panels --------------------------------------------------------------------

p1 + theme(panel.background = element_rect(fill = "white", colour = "grey50"))
p1 + theme(panel.border = element_rect(linetype = "dashed", fill = NA))
p1 + theme(panel.grid.major = element_line(colour = "black"))
p1 + theme(
  panel.grid.major.y = element_blank(),
  panel.grid.minor.y = element_blank()
)

# Put gridlines on top of data
p1 + theme(
  panel.background = element_rect(fill = NA),
  panel.grid.major = element_line(colour = "grey50"),
  panel.ontop = TRUE
)

# Axes ----------------------------------------------------------------------
p1 + theme(axis.line = element_line(size = 3, colour = "grey80"))
p1 + theme(axis.text = element_text(colour = "blue"))
p1 + theme(axis.ticks = element_line(size = 2))
p1 + theme(axis.ticks.length = unit(.25, "cm"))
p1 + theme(axis.title.y = element_text(size = rel(1.5), angle = 90))


# Legend --------------------------------------------------------------------
p2 <- ggplot(mtcars, aes(wt, mpg)) +
  geom_point(aes(colour = factor(cyl), shape = factor(vs))) +
  labs(
    x = "Weight (1000 lbs)",
    y = "Fuel economy (mpg)",
    colour = "Cylinders",
    shape = "Transmission"
   )
p2

# Position
p2 + theme(legend.position = "none")
p2 + theme(legend.justification = "top")
p2 + theme(legend.position = "bottom")

# Or place inside the plot using relative coordinates between 0 and 1
# legend.justification sets the corner that the position refers to
p2 + theme(
  legend.position = c(.95, .95),
  legend.justification = c("right", "top"),
  legend.box.just = "right",
  legend.margin = margin(6, 6, 6, 6)
)

# The legend.box properties work similarly for the space around
# all the legends
p2 + theme(
  legend.box.background = element_rect(),
  legend.box.margin = margin(6, 6, 6, 6)
)

# You can also control the display of the keys
# and the justifaction related to the plot area can be set
p2 + theme(legend.key = element_rect(fill = "white", colour = "black"))
p2 + theme(legend.text = element_text(size = 8, colour = "red"))
p2 + theme(legend.title = element_text(face = "bold"))

# Strips --------------------------------------------------------------------

p3 <- ggplot(mtcars, aes(wt, mpg)) +
  geom_point() +
  facet_wrap(~ cyl)
p3

p3 + theme(strip.background = element_rect(colour = "black", fill = "white"))
p3 + theme(strip.text.x = element_text(colour = "white", face = "bold"))
p3 + theme(panel.spacing = unit(1, "lines"))

Run the code above in your browser using DataCamp Workspace