Hi,I am going to need to output various results in a graph in C++.Is there some free/cheap graph plotting code that can be recommended for this purpose. I want it to be simple to use.Plus it needs to work with Visual Studio 2008, and perhaps handle 3D graphs (but this is not a necessity).I found thishttp://codecutter.org/tools/koolplot/but are there any other sugeestions?Cheers, Sam.

do a search 'graph library'

Gnuplot is a good tool and easy to call from C++. There are different ways of calling it from C++ . The simplest way I guess is to write to a text file from C++ code, and start gnuplot executable while passing the text file name as a command line parameter.

Sorry to threadjack: on a related note, what are the best tools/software components, preferably free but perhaps not, for contour/surface plotting? Excel is pretty good for everything else chart-related (2d scatter plots etc) but i find its surface charts aren't really up to scratch. Desiderata are:* Speed of rendering for large datasets* General XYZ data input (not restricted to a grid where rows/cols share the same x/y values)* Ability to plot 2 intersecting surfaces would be nice...* Good display of discontinuities (e.g. an implied volatility surface for a stock that pays discrete dividends)* Bonus points for looking pretty (i.e. suitable for production quality software, not just for research purposes - gnuplot doesn't seem to fit here)Excel addins, C++ libraries, C# components are all viable solutions... the intersected surfaces example at http://chartexamples.nevron.com looks pretty good (intersection feature is an optional bonus though)

For 2D what about thiszedgraph