Is there a C++ graphing library?
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04-10-2019 - |
Question
Is there a C++ graphing library that can display visual graphs (such as hyperbolas and parabolas and linear equations) based on the equation it is given and that is cross platform? Or am I just asking for too much...
Solution
Let's take your question step by step.
"based on the equation [that] it is given" This would require you to write an expression parser; C++ cannot interpret equations "on the fly" without you writing a procedure to do so. For this, I recommend you look at Bison (go straight to the example RPN calc to get the idea).
For the libraries, you can get any GUI toolkit for C++; there are dozens; the recommendation for QT is probably the most honest one. Check also Wikipedia. You need any toolkit which will provide you with a canvas where you can paint or render lines or splines. This is not trivial, but also not difficult.
Your program would probably work as follows:
- Get a mathematical expression (or the parameters for a known function; like the axes and center of an ellipse).
- Generate a set of points (this is done with a loop in C++)
- Pack those points and sent them to the paint or render method of your toolkit (with the appropriate scaling/normalization
Again, this is not trivial but not difficult either.
You are reinventing the wheel, but I commend you for that.
Cheers,
J.
OTHER TIPS
MathGL have expression parser and can plot function specified by textual formula (with a lot of special function included). Also you can create data set, fill it by formula and plot indirect functions (like ellipse, a*x^2+b*x^2=1).
If all you are interested in is the final output, rather than the programming side of things; you might want to try interfacing with something like gnuplot ( http://www.gnuplot.info/ ).
If you're interested in more, I'd recommend looking at their 'Links' page. This offers a bunch of either interface libraries and re-implementations (mostly for non-C languages from what I can see).
Hope that helps.