This is going to be grossly insufficient for anyone trying to learn R (a wonderfully powerful statistical package … although the “stats” part of that may be my inner statistician). This is merely a set of commands I tend to use myself on the rather too rare occasions when I need R.
R is started with “R” at the command-line … of course (although “r” does something quite different).
Loading Data
If you have a file formatted like :-
number1 number2 number3 number4
Then this can be read into a “variable” with :-
> Data <- read.table("filename.dat")
If it is convenient to add column names into the file to give presentable names later on, then do so and tell R that there are headers :-
> Data <- read.table("filename.dat", header=TRUE)
Whilst R has plenty of control about how to read data … far more than I need at least, it may be easiest to munge your input data into the above format if you are more comfortable with the command-line. You can see how R has imported your data with :-
> names(Data) [1]: "header1" "header2"
Later when it comes to doing something with the actual data, you can access the relevant “vector” with Data$header1. But hopefully you will choose more meaningful names!
Stats Summary
To produce a summary of a vector :-
> summary(vector) Min. 1st Qu. Median Mean 3rd Qu. Max. 1249 6938 18900 16210 24100 30840
Graphs
This section needs a lot of expansion. But to graph two variables … essentially one being a value at a particular time and the other being the time :-
plot(v1, v2, xlab="Horizontal label", ylab="Vertical label", main="Title")
This will draw the graph onto the default device – which is normally the main X11 display. If you want to change the output, you need to choose an alternate device. For a PNG file :-
png("filename.png")
(Redo the plot you're happy with)
dev.off()
