Calculating Adjacent matrix

hi to every one
i use this code to draw a graph
now i want to calculate adjacent matrix in calculating function i wrote in my mainwindow class.
do you have any idea ?
how can i do it?
can you explain me this code more because i don't write it , i was changing it a little to create more than one line
thanks a lot
bye
http://288993.20upload.net/files/1389/bahman/Graph2.rar

Sorry, this is not the place to ask for explanations on code you found somewhere on the web. How about asking the author of that code?
For general information on how to calculate an adjacency matrix, I'd like to refer you to the math section of your nearest university library, the almighty interweb or I'd like to suggest you simply use the Boost::graph library.