In this section, we'll focus on an introduction to EasyPlot. So, we're going to be installing the gnuplot command-line tool and the EasyPlot Haskell library. EasyPlot is just a Haskell wrapper for gnuplot. It allows us to interact with the gnuplotting utility from within Haskell and our IHaskell environment. We need data, and for that we're going to be pulling data from Yahoo Finance. I like Yahoo Finance because I can obtain the full history of any publicly traded company; and in this section, we're going to end with our first plot. Let's go to our Terminal, but first we need to install gnuplot. The command is as follows:

Now, let's do a cabal update and then cabal install EasyPlot, as shown in the following example:

If you didn't get any error messages, that means you're ready to go. Now we need data;...