geom_errorbar {ggplot2} | R Documentation |
Error bars.
geom_errorbar(mapping = NULL, data = NULL, stat = "identity", position = "identity", ...)
mapping |
The aesthetic mapping, usually constructed
with |
data |
A layer specific dataset - only needed if you want to override the plot defaults. |
stat |
The statistical transformation to use on the data for this layer. |
position |
The position adjustment to use for overlappling points on this layer |
... |
other arguments passed on to
|
geom_errorbar
understands the following aesthetics (required aesthetics are in bold):
x
ymax
ymin
alpha
colour
linetype
size
width
geom_pointrange
: range indicated by
straight line, with point in the middle;
geom_linerange
: range indicated by straight
line; geom_crossbar
: hollow bar with middle
indicated by horizontal line; stat_summary
:
examples of these guys in use, geom_smooth
for continuous analog
# Create a simple example dataset df <- data.frame( trt = factor(c(1, 1, 2, 2)), resp = c(1, 5, 3, 4), group = factor(c(1, 2, 1, 2)), se = c(0.1, 0.3, 0.3, 0.2) ) df2 <- df[c(1,3),] # Define the top and bottom of the errorbars limits <- aes(ymax = resp + se, ymin=resp - se) p <- ggplot(df, aes(fill=group, y=resp, x=trt)) p + geom_bar(position="dodge", stat="identity") # Because the bars and errorbars have different widths # we need to specify how wide the objects we are dodging are dodge <- position_dodge(width=0.9) p + geom_bar(position=dodge) + geom_errorbar(limits, position=dodge, width=0.25) p <- ggplot(df2, aes(fill=group, y=resp, x=trt)) p + geom_bar(position=dodge) p + geom_bar(position=dodge) + geom_errorbar(limits, position=dodge, width=0.25) p <- ggplot(df, aes(colour=group, y=resp, x=trt)) p + geom_point() + geom_errorbar(limits, width=0.2) p + geom_pointrange(limits) p + geom_crossbar(limits, width=0.2) # If we want to draw lines, we need to manually set the # groups which define the lines - here the groups in the # original dataframe p + geom_line(aes(group=group)) + geom_errorbar(limits, width=0.2)