coord_capped_cart {lemon}

Cartesian coordinates with capped axis lines.

Description

Caps the axis lines to the outer ticks to e.g. indicate range of values. Methods correspond to coord_cartesian and coord_flip

Usage

coord_capped_cart(
  xlim = NULL,
  ylim = NULL,
  expand = TRUE,
  top = waiver(),
  left = waiver(),
  bottom = waiver(),
  right = waiver(),
  gap = 0.01
)

coord_capped_flip(
  xlim = NULL,
  ylim = NULL,
  expand = TRUE,
  top = waiver(),
  left = waiver(),
  bottom = waiver(),
  right = waiver(),
  gap = 0.01
)

capped_horizontal(capped = c("both", "left", "right", "none"), gap = 0.01)

capped_vertical(capped = c("top", "bottom", "both", "none"), gap = 0.01)

Arguments

xlim, ylim

Limits for the x and y axes.

expand

If TRUE, the default, adds a small expansion factor to the limits to ensure that data and axes don't overlap. If FALSE, limits are taken exactly from the data or xlim/ylim.

top, left, bottom, right

Either a function returned from capped_horizontal or brackets_horizontal. If string, it is assumed to be shorthand for capped_horizontal(capped) or similar for vertical.

gap

Both ends are always capped by this proportion. Usually a value between 0 and 1.

capped

Which end to cap the line. Can be one of (where relevant): both, none, left, right, top, bottom.

Details

This function is a simple override of coord_flex_cart and coord_flex_flip, which allows shorthand specification of what to cap.

NB! A panel-border is typically drawn on top such that it covers tick marks, grid lines, and axis lines. Many themes also do not draw axis lines. To ensure the modified axis lines are visible, use theme(panel.border=element_blank(), axis.lines=element_line()).

Examples

library(ggplot2)
# Notice how the axis lines of the following plot meet in the lower-left corner.
p <- ggplot(mtcars, aes(x = mpg)) + geom_dotplot() +
  theme_bw() +
  theme(panel.border=element_blank(), axis.line=element_line())
p

# We can introduce a gap by capping the ends:
p + coord_capped_cart(bottom='none', left='none')

# The lower limit on the y-axis is 0. We can cap the line to this value.
# Notice how the x-axis line extends through the plot when we no long
# define its capping.
p + coord_capped_cart(left='both')

# It it also works on the flipped.
p + coord_capped_flip(bottom='both')

# And on secondary axis, in conjuction with brackets:
p +
  scale_y_continuous(sec.axis = sec_axis(~.*100)) +
  scale_x_continuous(sec.axis = sec_axis(~1/., name='Madness scale')) +
  coord_capped_cart(bottom='none', left='none', right='both', top=brackets_horizontal())
# Although we cannot recommend the above madness.