Make graphs on Qt and plot your arduino measurements

As promised I come in my second instructable to explain you how to program graphs on Qt. This will allow you to monitor measurements from a probe plug on your arduino. At the end of this instructable you will be able to program Labview-like software for free.

In this instructable you will learn :
how to receive data from your arduino
how to plot them on a graph

To do this I use Qt (say cute) which I already presented in my former instructable :
Control your arduino from your PC with the Qt Gui

To start to write your programs you will need to:
install Qt (sounds obvious ;) ) : https://qt.nokia.com/products/
install the additional library to read the port com : see my former instructable
install the additional library to put graphs in your programs : see the next step.

PS : As you probably notice it, I am not a native English speaker. I would be please if you can correct me.

Step 1 Installation of QWT

Qwt is a additional library which allows you to add graph in your qt program.

I assume that you have already installed Qt, and you have basic skills in programming in C/C++.

First you need to get qwt from source-forge : http://sourceforge.net/projects/qwt/

Then you extract the files.

Here comes the tricky part. The files you downloaded are not compiled.
So you must compiled them. To do so you must start the Qt prompt console.
You can find it on Windows in :
start menu,
Qt SDK,
Desktop,
Qt 4.7.3 for Desktop (MinGW)

Then send the command that are on picture 2.

Congratulation, you perfectly compiled the library!