geom_path: Connect observations.

Description

geom_path() connects the observations in the order in which they appear in the data. geom_line() connects them in order of the variable on the x axis. geom_step() creates a stairstep plot, highlighting exactly when changes occur.

Usage

geom_path(mapping = NULL, data = NULL, stat = "identity",
  position = "identity", lineend = "butt", linejoin = "round",
  linemitre = 1, na.rm = FALSE, arrow = NULL, show.legend = NA,
  inherit.aes = TRUE, ...)
geom_line(mapping = NULL, data = NULL, stat = "identity",
  position = "identity", na.rm = FALSE, show.legend = NA,
  inherit.aes = TRUE, ...)
geom_step(mapping = NULL, data = NULL, stat = "identity",
  position = "identity", direction = "hv", na.rm = FALSE,
  show.legend = NA, inherit.aes = TRUE, ...)

Arguments

mapping

Set of aesthetic mappings created by aes or aes_. If specified and inherit.aes = TRUE (the default), is combined with the default mapping at the top le

data

A data frame. If specified, overrides the default data frame defined at the top level of the plot.

stat

The statistical transformation to use on the data for this layer, as a string.

position

Position adjustment, either as a string, or the result of a call to a position adjustment function.

lineend

Line end style (round, butt, square)

linejoin

Line join style (round, mitre, bevel)

linemitre

Line mitre limit (number greater than 1)

na.rm

If FALSE (the default), removes missing values with a warning. If TRUE silently removes missing values.

arrow

Arrow specification, as created by arrow

show.legend

logical. Should this layer be included in the legends? NA, the default, includes if any aesthetics are mapped. FALSE never includes, and TRUE always includes.

inherit.aes

If FALSE, overrides the default aesthetics, rather than combining with them. This is most useful for helper functions that define both data and aesthetics and shouldn't inherit behaviour from the default plot specification, e.g.

...

other arguments passed on to layer. There are three types of arguments you can use here:

Aesthetics: to set an aesthetic to a fixed value, likecolor = "red"orsize = 3.

direction

direction of stairs: 'vh' for vertical then horizontal, or 'hv' for horizontal then vertical

Aesthetics

[results=rd,stage=build]{ggplot2:::rd_aesthetics("geom", "path")} # geom_line() is suitable for time series ggplot(economics, aes(date, unemploy)) + geom_line() ggplot(economics_long, aes(date, value01, colour = variable)) + geom_line()

# geom_step() is useful when you want to highlight exactly when # the y value chanes recent <- economics[economics$date > as.Date("2013-01-01"), ] ggplot(recent, aes(date, unemploy)) + geom_line() ggplot(recent, aes(date, unemploy)) + geom_step()

# geom_path lets you explore how two variables are related over time, # e.g. unemployment and personal savings rate m <- ggplot(economics, aes(unemploy/pop, psavert)) m + geom_path() m + geom_path(aes(colour = as.numeric(date)))

# Changing parameters ---------------------------------------------- ggplot(economics, aes(date, unemploy)) + geom_line(colour = "red")

# Use the arrow parameter to add an arrow to the line # See ?arrow for more details c <- ggplot(economics, aes(x = date, y = pop)) c + geom_line(arrow = arrow()) c + geom_line( arrow = arrow(angle = 15, ends = "both", type = "closed") )

# Control line join parameters df <- data.frame(x = 1:3, y = c(4, 1, 9)) base <- ggplot(df, aes(x, y)) base + geom_path(size = 10) base + geom_path(size = 10, lineend = "round") base + geom_path(size = 10, linejoin = "mitre", lineend = "butt")

# NAs break the line. Use na.rm = T to suppress the warning message df <- data.frame( x = 1:5, y1 = c(1, 2, 3, 4, NA), y2 = c(NA, 2, 3, 4, 5), y3 = c(1, 2, NA, 4, 5) ) ggplot(df, aes(x, y1)) + geom_point() + geom_line() ggplot(df, aes(x, y2)) + geom_point() + geom_line() ggplot(df, aes(x, y3)) + geom_point() + geom_line()

# Setting line type vs colour/size # Line type needs to be applied to a line as a whole, so it can # not be used with colour or size that vary across a line x <- seq(0.01, .99, length.out = 100) df <- data.frame( x = rep(x, 2), y = c(qlogis(x), 2 * qlogis(x)), group = rep(c("a","b"), each = 100) ) p <- ggplot(df, aes(x=x, y=y, group=group)) # These work p + geom_line(linetype = 2) p + geom_line(aes(colour = group), linetype = 2) p + geom_line(aes(colour = x)) # But this doesn't should_stop(p + geom_line(aes(colour = x), linetype=2))

geom_polygon: Filled paths (polygons); geom_segment: Line segments