// Ceres Solver - A fast non-linear least squares minimizer
// Copyright 2026 Google Inc. All rights reserved.
// http://ceres-solver.org/
//
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//
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// Author: hellston20a@gmail.com (H S Helson Go)

#ifndef CERES_PUBLIC_CONSTANTS_H_
#define CERES_PUBLIC_CONSTANTS_H_

// TODO(HSHelson): This header should no longer be necessary once C++20's
// <numbers> (e.g. std::numbers::pi_v) becomes usable

// The constants are computed using mpmath by the following shell command:
//
// python3 - <<EOF
// from mpmath import mp
// mp.dps = 64
// print(mp.pi)
// print(mp.sqrt(3))
// EOF
namespace ceres::constants {
// π
template <typename T>
inline constexpr T pi_v(
    3.141592653589793238462643383279502884197169399375105820974944592L);
inline constexpr double pi = pi_v<double>;
// √3
template <typename T>
inline constexpr T sqrt_3_v(
    1.732050807568877293527446341505872366942805253810380628055806979L);
inline constexpr double sqrt_3 = sqrt_3_v<double>;
}  // namespace ceres::constants

#endif  // CERES_PUBLIC_CONSTANTS_H_