To print a listing of all examples of a chapter, use ch17()
.
To run all the examples of ch17()
, use example(ch17)
.
Examples
if (interactive()) {
# Chapter 17 - Creating Faceted Graphics with Lattice
# Creating a Lattice Plot
str(mtcars)
## Loading the lattice package
library("lattice")
## Making a lattice scatterplot
xyplot(mpg ~ hp | factor(cyl), data=mtcars)
## Adding trend lines
xyplot(mpg ~ hp | factor(cyl), data=mtcars,
type=c("p", "r"))
# Changing Plot Options
## Adding titles and labels
xyplot(mpg ~ hp | factor(cyl), data=mtcars,
type=c("p", "r"),
main="Fuel economy vs. Performance",
xlab="Performance (horse power)",
ylab="Fuel economy (miles per gallon)",
)
xyplot(mpg ~ hp | factor(cyl), data=mtcars,
type=c("p", "r"),
main=list(
label="Fuel economy vs. Performance given Number of Cylinders",
cex=0.75)
)
## Changing the font size of titles and labels
xyplot(mpg ~ hp | factor(cyl), data=mtcars,
type=c("p", "r"),
main=list(
label="Fuel economy vs. Performance given Number of Cylinders",
cex=0.75),
xlab=list(
label="Performance (horse power)",
cex=0.75),
ylab=list(
label="Fuel economy (miles per gallon)",
cex=0.75),
scales=list(cex=0.5)
)
## Using themes to modify plot options
xyplot(mpg ~ hp | factor(cyl), data=mtcars,
type=c("p", "r"),
par.settings=simpleTheme(col="red", col.line="blue")
)
# Plotting Different Types
## Making a bar chart
mtcars$cars <- rownames(mtcars)
barchart(cars ~ mpg | factor(cyl), data=mtcars,
main="barchart",
scales=list(cex=0.5),
layout=c(3, 1)
)
## Making a box-and-whisker plot
bwplot(~ hp | factor(cyl), data=mtcars, main="bwplot")
# Plotting Data in Groups
## Using data in tall format
str(longley)
library("reshape2")
mlongley <- melt(longley, id.vars="Year")
str(mlongley)
xyplot(value ~ Year | variable, data=mlongley,
layout=c(6, 1),
par.strip.text=list(cex=0.7),
scales=list(cex=0.7)
)
## Creating a chart with groups
mtcars$cars <- rownames(mtcars)
mtcars$am <- with(mtcars, ifelse(am==0, "Automatic", "Manual"))
barchart(cars ~ mpg | factor(cyl), data=mtcars,
group=am,
scales=list(cex=0.5),
layout=c(3, 1),
)
## Adding a key
barchart(cars ~ mpg | factor(cyl), data=mtcars,
main="barchart with groups",
group=am,
auto.key=TRUE,
par.settings = simpleTheme(col=c("grey80", "grey20")),
scales=list(cex=0.5),
layout=c(3, 1)
)
# Printing and Saving a Lattice Plot
## Assigning a lattice plot to an object
my.plot <- xyplot(mpg ~ hp | cyl, data=mtcars)
class(my.plot)
## Printing a lattice plot in a script
xyplot(mpg ~ hp | cyl, data=mtcars)
my.plot <- xyplot(mpg ~ hp | cyl, data=mtcars)
print(my.plot)
## Saving a lattice plot to file
filename <- file.path(tempdir(), "xyplot")
if (FALSE) {
trellis.device(device="png", filename=filename)
}
print(my.plot)
if (FALSE) {
dev.off()
}
}