geom_path(mapping = NULL, data = NULL, stat = "identity",
position = "identity", lineend = "butt", linejoin = "round",
linemitre = 1, na.rm = FALSE, arrow = NULL, ...)
aes
or aes_string
. Only needs to be set
at the layer level if you are overriding the plot defaults.FALSE
(the default), removes missing values with
a warning. If TRUE
silently removes missing values.# Add aesthetic mappings p + geom_path(aes(size = year)) p + geom_path(aes(colour = year))
# Change scale p + geom_path(aes(size = year)) + scale_size(range = c(1, 3))
# Set aesthetics to fixed value p + geom_path(colour = "green")
# 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")
# Use qplot instead qplot(length, rating, data=myear, geom="path")
# Using economic data: # How is unemployment and personal savings rate related? qplot(unemploy/pop, psavert, data=economics) qplot(unemploy/pop, psavert, data=economics, geom="path") qplot(unemploy/pop, psavert, data=economics, geom="path", size=as.numeric(date))
# How is rate of unemployment and length of unemployment? qplot(unemploy/pop, uempmed, data=economics) qplot(unemploy/pop, uempmed, data=economics, geom="path") qplot(unemploy/pop, uempmed, data=economics, geom="path") + geom_point(data=head(economics, 1), colour="red") + geom_point(data=tail(economics, 1), colour="blue") qplot(unemploy/pop, uempmed, data=economics, geom="path") + geom_text(data=head(economics, 1), label="1967", colour="blue") + geom_text(data=tail(economics, 1), label="2007", colour="blue")
# geom_path removes missing values on the ends of a 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), y4 = c(1, 2, 3, 4, 5)) qplot(x, y1, data = df, geom = c("point","line")) qplot(x, y2, data = df, geom = c("point","line")) qplot(x, y3, data = df, geom = c("point","line")) qplot(x, y4, data = df, geom = c("point","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=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))
# Should work p + geom_line(linetype = 2) p + geom_line(aes(colour = group), linetype = 2) p + geom_line(aes(colour = x))
# Should fail should_stop(p + geom_line(aes(colour = x), linetype=2))
# Use the arrow parameter to add an arrow to the line # See ?grid::arrow for more details library(grid) c <- ggplot(economics, aes(x = date, y = pop)) # Arrow defaults to "last" c + geom_path(arrow = arrow()) c + geom_path(arrow = arrow(angle = 15, ends = "both", length = unit(0.6, "inches")))
geom_line
: Functional (ordered) lines;
geom_polygon
: Filled paths (polygons);
geom_segment
: Line segments