Does the C++ Standard Library define pi?

Question

Does STL contain definition for pi (=3.14...)? Certainly, I can use old good M_PI, but it is non-standard and not cross-compiler compliant.

Answer 1

Boost.Math defines pi (and many other) mathematical constants to very high precision

#include <boost/math/constants.hpp>
long double pi = boost::math::constants::pi<long double>();

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