R is a statistics program. I can calculate statistical functions and draw nice graphs. Today I used it for showing some graphs.
I use R on my linux system, but it also works on Windows. To install it look at website of R.
Data from a file can be read with the function
filename is the name of filename that you want to read. This would look like:
visitors <- read.table('visitors.dat')
visitors.dat should contains two columns like this:
id visitors 1 100 2 204 3 70 4 79 5 99 6 100 ... ...
You can also use the
read.csv(filename) function. This will read comma
separated values files.
When the file is read, the data will be put in a table named
because of the variable and the
<- operator. Typing
visitors on the R
prompt will show the contents of the table. To plot the data, type
plot(visitors). It's that easy. Plot will choose a way to show the data.
After plot you can type
lines(visitors) to add the lines to connect the dots.
It's also possible to add a line to show to the trend in the data:
Which will add a green line to the plot, showing the trend.
That's it. Please don't ask me questions about statistics, because I have no idea at the moment. I want to know more about it and will find some books and information.
The R program can do much, this is just the beginning of the possibilities. Of course there are many uses for statistics, like performance of your program.