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The inspiration to write this code was to have an
easy-to-use parser for functions given as string. You have a string like
"cos(x)-7*x/(1+x)"
and you want to compute some values, maybe for displaying
the graph of the function. You can write code like this:
CFunction<longdouble>* fkt =
CFunction<longdouble>::Parse("cos(x)-7*x/(1+x)");
longdouble y = fkt->Execute(1.5);
There are lots of definitions in the background, but the
result is easy and fast! There is a one-time pasing step to construct the
function tree, and function evaluations are only calls of standard math
functions like sin, +, *, sqrt. When you want to know details about the
implementaion, you should look into the source code. It would be too complex to
describe the parsing algorithm here.
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