ggplot2 (version 2.2.1)

position_dodge: Dodge overlapping objects side-to-side

Description

Dodging preserves the vertical position of an geom while adjusting the horizontal position.

Usage

position_dodge(width = NULL)

Arguments

width

Dodging width, when different to the width of the individual elements. This is useful when you want to align narrow geoms with wider geoms. See the examples.

See Also

Other position adjustments: position_identity, position_jitterdodge, position_jitter, position_nudge, position_stack

Examples

ggplot(mtcars, aes(factor(cyl), fill = factor(vs))) +
  geom_bar(position = "dodge")

ggplot(diamonds, aes(price, fill = cut)) +
  geom_histogram(position="dodge")
# see ?geom_boxplot and ?geom_bar for more examples

# In this case a frequency polygon is probably a better choice
ggplot(diamonds, aes(price, colour = cut)) +
  geom_freqpoly()


# Dodging with various widths -------------------------------------
# To dodge items with different widths, you need to be explicit
df <- data.frame(x = c("a","a","b","b"), y = 2:5, g = rep(1:2, 2))
p <- ggplot(df, aes(x, y, group = g)) +
  geom_col(position = "dodge", fill = "grey50", colour = "black")
p

# A line range has no width:
p + geom_linerange(aes(ymin = y - 1, ymax = y + 1), position = "dodge")

# So you must explicitly specify the width
p + geom_linerange(
  aes(ymin = y - 1, ymax = y + 1),
  position = position_dodge(width = 0.9)
)

# The same principle applies to error bars, which are usually
# narrower than the bars
p + geom_errorbar(
  aes(ymin = y - 1, ymax = y + 1),
  width = 0.2,
  position = "dodge"
)
p + geom_errorbar(
  aes(ymin = y - 1, ymax = y + 1),
  width = 0.2,
  position = position_dodge(width = 0.9)
)