# CPUReg1 Example -- cpureg1.r source code

# Read data from input file.
cpudat = read.table(file="cpu.txt", header=T, skip=8)

# Print data frame.
cat("cpudat Dataset:\n")
print(cpudat)

# Obtain univariate statistics and correlation.
cat("Means:\n")
print(mean(cpudat))
cat("Standard Deviations:\n")
print(sd(cpudat))
cat("Correlation:\n")
print(cor(cpudat))

# Obtain simple regression model information.
model = lm(CpuTime ~ LinesOut, data=cpudat)

cat("Regression Summary of Bears Dataset:\n")
print(summary(model))

# Get residuals and predicted values.
r = residuals(model)
p = fitted(model)

attach(cpudat)
pdf("cpureg1.pdf")

# Create scatter plot of CpuTime vs. LinesOut.
plot(LinesOut, y=CpuTime, 
	         main="Scatterplot of CpuTime vs. LinesOut",
           xlab="CPU Time in Seconds",
           ylab="Output Lines")

# Create residual plot.
plot(p, r, main="Residual Plot for CPU Dataset",
           xlab="Predicted Values",
           ylab="Residuals")

# Create normal plot.           
qqnorm(r, main="Normal Plot for CPU Dataset")

dev.off( )