Better than pretty

Pretty R is a syntax formatter for R, it generates highlighted and properly indented R code suitable for including in an HTML document.  Better yet, all the R keywords are linked back to an online reference manual at inside-r.org!  Check it out.

# multiple comparison with aov 
 
s <- read.table("dogFoodSales.txt",header=T)
 
# fit the ANOVA model and perform post hoc test (Tukey's HSD)
 
print( summary( smodel <- aov(sales ~ location, data=s) ) )
print( TukeyHSD(smodel,"location", ordered=TRUE) )
 
# check residuals for normality
 
qqnorm(smodel$residuals)
qqline(smodel$residuals)
print(shapiro.test(smodel$residuals))
 
# check for homogeneity of variance
 
attach(s)
print(bartlett.test(sales ~ location))
 
# just in case, verify with nonparametric test
 
print(kruskal.test(sales ~ location))
 
detach(s)

Tip from the R Bloggers.

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