Regards plotting in C++ for anyone who didn't do it yet. I will say what I did to plot Graphs in C++
Download the zipped file "gp443win32.zip" from http://sourceforge.jp/projects/sfnet_gnuplot/downloads/gnuplot/4.4.3/gp443win32.zip/
Extract it in "C:\Gnuplot"
then I read "C:\Gnuplot\gnuplot\README.Windows"
and I got these information:
I used Windows 7 ==> so you need to download "winhlp32.exe"... just search for it "winhlp32.exe Windows 7" in a search engine and go through the first link.
Append to the "Path" Environment variable the path for binary folder which is "C:\Gnuplot\gnuplot\binary"
then I shutdown my computer and open it again. After I found that it didn't sense the change in the environment variables :D
you need now to write a sample code to test your plotting ability :)
so you can visit this link
http://code.google.com/p/gnuplot-cpp/source/browse/#svn%2Ftrunk
to see the header file "gnuplot_i.hpp" and source file "example.cc".
You will get many and many graphs, choose your appropriate graph, customize your core, and enjoy :)