libfparser-4.3 binary package in Ubuntu Precise amd64

 This C++ library offers a class which can be used to parse and evaluate a
 mathematical function from a string (which might be eg. requested from the
 user). The syntax of the function string is similar to mathematical
 expressions written in C/C++ (the exact syntax is specified later in this
 document). The function can then be evaluated with different values of
 variables.
 .
 For example, a function like "sin(sqrt(x*x+y*y))" can be parsed from a
 string (either std::string or a C-style string) and then evaluated with
 different values of x and y. This library can be useful for evaluating
 user-inputted functions, or in some cases interpreting mathematical
 expressions in a scripting language.

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