Graphics Reference
In-Depth Information
Figure 2-7. Left: bar graph of counts with qplot() with continuous x variable; right: with x variable
converted to a factor
If the vector is in a data frame, you can use the following syntax:
# Bar graph of values. This uses the BOD data frame, with the
#"Time" column for x values and the "demand" column for y values.
qplot(Time, demand, data
=
BOD, geom
=
"bar"
, stat
=
"identity"
)
# This is equivalent to:
ggplot(BOD, aes(x
=
Time, y
=
demand))
+
geom_bar(stat
=
"identity"
)
# Bar graph of counts
qplot(factor(cyl), data
=
mtcars)
# This is equivalent to:
ggplot(mtcars, aes(x
=
factor(cyl)))
+
geom_bar()
See Also
See
Chapter 3
for more in-depth information about creating bar graphs.
Creating a Histogram
Problem
You want to view the distribution of one-dimensional data with a histogram.
Solution
