Rcode snippets

Add legend in plot

legend(c("bottomright"),legend=c("Group1","Group2","Group3"),lwd=c(2.5,2.5),col=c("red","green","blue"))

What colors are there?

http://www.stat.columbia.edu/~tzheng/files/Rcolor.pdf

Sort data frame by some column or row

sorting examples using the mtcars dataset

attach(mtcars)

sort by mpg

newdata <- mtcars[order(mpg),]

sort by mpg and cyl

newdata <- mtcars[order(mpg, cyl),]

sort by mpg (ascending) and cyl (descending)

newdata <- mtcars[order(mpg, -cyl),]

detach(mtcars)