# AutoSales3 -- Create barplots of the one week sales of automobiles.

# Read car and truck values from tab-delimited autos.dat
autos <- read.table("autos.txt", header=T, sep="\t") 

# Start PNG device driver to save output to disk.
pdf("autosales3.pdf")
   
# Graph cars with specified labels for axes.  Use blue 
# borders and diagnal lines in bars.
barplot(autos$cars, main="AutoSales3 Example: Cars Only", 
   names.arg=autos$days, border="blue", xlab="Day of Week",
   ylab="Number of Cars Sold", density=c(5, 10, 15, 20, 25)) 
   
# Graph autos with adjacent bars using rainbow colors
barplot(as.matrix(autos[,-1]), xlab="Automobile Categories",
   ylab="One Week Sales of Vehicles", beside=TRUE, col=rainbow(5),
   main="AutoSales3 Example: Side-by-side Bar Graph")

# Place the legend at the top-left corner with no frame  
# using rainbow colors
legend("topleft", legend=autos$days, cex=1.3, bty="n", fill=rainbow(5));

# Expand right side of clipping rect to make room for the legend
par(xpd=T, mar=par()$mar+c(0,0,0,4))

# Graph autos (transposing the matrix) using heat colors,  
# put 10% of the space between each bar, and make labels  
# smaller with horizontal y-axis labels
barplot(t(autos[,-1]), main="AutoSales3 Example: Stacked Bar Graph", 
   ylab="One Week Sales of Automobiles", col=heat.colors(3), 
   space=0.1, cex.axis=0.8, las=1, names.arg=autos$days, cex=0.8) 
   
# Place the legend at (6,30) using heat colors
legend(6, 30, names(autos), cex=0.8, fill=heat.colors(3))
   
# Restore default clipping rect
par(mar=c(5, 4, 4, 2) + 0.1)

# Turn off device driver (to flush output to png)
dev.off()