geom_vline

Line, vertical.

This geom allows you to annotate the plot with vertical lines (see geom_hline and geom_abline for other types of lines.

Usage

geom_vline(mapping = NULL, data = NULL, stat = "vline",
    position = "identity", show_guide = FALSE, ...)

Details

There are two ways to use it. You can either specify the intercept of the line in the call to the geom, in which case the line will be in the same position in every panel. Alternatively, you can supply a different intercept for each panel using a data.frame. See the examples for the differences.

See Also

geom_hline for horizontal lines, geom_abline for lines defined by a slope and intercept, geom_segment for a more general approach"

Aliases

• geom_vline

Examples

# Fixed lines
p <- ggplot(mtcars, aes(x = wt, y = mpg)) + geom_point()
p + geom_vline(xintercept = 5)
p + geom_vline(xintercept = 1:5)
p + geom_vline(xintercept = 1:5, colour="green", linetype = "longdash")
p + geom_vline(aes(xintercept = wt))

# With coordinate transforms
p + geom_vline(aes(xintercept = wt)) + coord_equal()
p + geom_vline(aes(xintercept = wt)) + coord_flip()
p + geom_vline(aes(xintercept = wt)) + coord_polar()

p2 <- p + aes(colour = factor(cyl))
p2 + geom_vline(xintercept = 15)

# To display different lines in different facets, you need to
# create a data frame.
p <- qplot(mpg, wt, data=mtcars, facets = vs ~ am)
vline.data <- data.frame(z = c(15, 20, 25, 30), vs = c(0, 0, 1, 1), am = c(0, 1, 0, 1))
p + geom_vline(aes(xintercept = z), vline.data)