While searching for a good 3d plotting framework for my product, I stumbled upon this tool GNUPlot.
GNUPlot is an awesome tool which does a wonderful job of rendering as plot, your 2d functions and data , what more could you ask , it goes ahead of my expectations to plot 2d projecttions of 3d surfaces and data.
Among all the features like changing the X,Y axes labels, setting ranges, number of samples to take,
setting title, line types, colors, screen size, I liked the terminal type the most.
With this feature you can actually plot your data to any device, include you HP printer sitting at the corner of your office floor.
Termincal type for MS Windows is surprising enough named as window and X11 for *nix,.
Plots can be exported to png, postrcript, aifm (Adobe Illustrator ), corel (Corel Draw) files to name a few.
For example to get a postscript file of your plot, all you have to do is
set terminal postscript
set output “sample.png”
plot {<function>| {“file”}>
I will be posting a series of blog in the coming day on GNUPlot, with new discoveries am going to make in this tool.
Licensing :
This seems to be a boring topic, which often takes software engineers to yawning, nevertheless it is the most important criteria when you select a piece of software to be used in your development of product.
You might not want to call unsolicited legalities 
While the name GNUPlot hints that this software is covered under GPL Licence, ironically it is not.
Although it is free which allows you to use, copy and modify it, authors Thomas Williams, Colin Kelley restricts you from redistributing it with modifications.
Still you can redistribute your changes and modifications as a separate patch, with the source code.
And the nest part of this license is that you can use it in you commmercial software product
