Standard library header <numbers> (C++20)

 

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This header is part of the numeric library.

Mathematical constants(since C++20)

The header <numbers> provides several mathematical constants, such as std::numbers::pi or std::numbers::sqrt2

Synopsis

namespace std::numbers{template<class T>inlineconstexpr T e_v =/* unspecified */;template<class T>inlineconstexpr T log2e_v =/* unspecified */;template<class T>inlineconstexpr T log10e_v =/* unspecified */;template<class T>inlineconstexpr T pi_v =/* unspecified */;template<class T>inlineconstexpr T inv_pi_v =/* unspecified */;template<class T>inlineconstexpr T inv_sqrtpi_v =/* unspecified */;template<class T>inlineconstexpr T ln2_v =/* unspecified */;template<class T>inlineconstexpr T ln10_v =/* unspecified */;template<class T>inlineconstexpr T sqrt2_v =/* unspecified */;template<class T>inlineconstexpr T sqrt3_v =/* unspecified */;template<class T>inlineconstexpr T inv_sqrt3_v =/* unspecified */;template<class T>inlineconstexpr T egamma_v =/* unspecified */;template<class T>inlineconstexpr T phi_v =/* unspecified */;   template<floating_point T>inlineconstexpr T e_v<T>=/* see description */;template<floating_point T>inlineconstexpr T log2e_v<T>=/* see description */;template<floating_point T>inlineconstexpr T log10e_v<T>=/* see description */;template<floating_point T>inlineconstexpr T pi_v<T>=/* see description */;template<floating_point T>inlineconstexpr T inv_pi_v<T>=/* see description */;template<floating_point T>inlineconstexpr T inv_sqrtpi_v<T>=/* see description */;template<floating_point T>inlineconstexpr T ln2_v<T>=/* see description */;template<floating_point T>inlineconstexpr T ln10_v<T>=/* see description */;template<floating_point T>inlineconstexpr T sqrt2_v<T>=/* see description */;template<floating_point T>inlineconstexpr T sqrt3_v<T>=/* see description */;template<floating_point T>inlineconstexpr T inv_sqrt3_v<T>=/* see description */;template<floating_point T>inlineconstexpr T egamma_v<T>=/* see description */;template<floating_point T>inlineconstexpr T phi_v<T>=/* see description */;   inlineconstexprdouble e = e_v<double>;inlineconstexprdouble log2e = log2e_v<double>;inlineconstexprdouble log10e = log10e_v<double>;inlineconstexprdouble pi = pi_v<double>;inlineconstexprdouble inv_pi = inv_pi_v<double>;inlineconstexprdouble inv_sqrtpi = inv_sqrtpi_v<double>;inlineconstexprdouble ln2 = ln2_v<double>;inlineconstexprdouble ln10 = ln10_v<double>;inlineconstexprdouble sqrt2 = sqrt2_v<double>;inlineconstexprdouble sqrt3 = sqrt3_v<double>;inlineconstexprdouble inv_sqrt3 = inv_sqrt3_v<double>;inlineconstexprdouble egamma = egamma_v<double>;inlineconstexprdouble phi = phi_v<double>;}