# Trellis Examples
library(lattice)
attach(mtcars)
names(mtcars)

# create factors with value labels
gear.f<-factor(gear,levels=c(3,4,5),labels=c("3gears","4gears","5gears"))
cyl.f <-factor(cyl,levels=c(4,6,8),labels=c("4cyl","6cyl","8cyl"))

# kernal density plot
densityplot(~mpg,main="Density Plot",xlab="Miles per Gallon")

# kernal density plots by factor level
densityplot(~mpg|cyl.f,main="Density Plot by Number of Cylinders",xlab="Miles per Gallon")

# kernal density plots by factor level (alternate layout)
densityplot(~mpg|cyl.f,main="Density Plot by Numer of Cylinders",xlab="Miles per Gallon",layout=c(1,3))

# boxplots for each combination of two factors
bwplot(cyl.f~mpg|gear.f,
ylab="Cylinders", xlab="Miles per Gallon",main="Mileage by Cylinders and Gears",layout=(c(1,3)))

# scatterplots for each combination of two factors
xyplot(mpg~wt|cyl.f*gear.f,main="Scatterplots by Cylinders and Gears",ylab="Miles per Gallon", xlab="Car Weight")

# 3d scatterplot by factor level
cloud(mpg~wt*qsec|cyl.f,main="3D Scatterplot by Cylinders")

#3d wireframe
x <- seq(-pi, pi, len = 20) 
y <- seq(-pi, pi, len = 20) 
g <- expand.grid(x = x, y = y) 
g$z <- sin(sqrt(g$x^2 + g$y^2)) 
wireframe(z ~ x * y, g, drape = TRUE, aspect = c(3,1), colorkey = TRUE,main=expression(paste(z==sin(sqrt(x^2+y^2)))))