diff options
Diffstat (limited to 'boost/math/special_functions/detail/bessel_jy_asym.hpp')
| -rw-r--r-- | boost/math/special_functions/detail/bessel_jy_asym.hpp | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/boost/math/special_functions/detail/bessel_jy_asym.hpp b/boost/math/special_functions/detail/bessel_jy_asym.hpp index 81f6238e58..4d7ac485ad 100644 --- a/boost/math/special_functions/detail/bessel_jy_asym.hpp +++ b/boost/math/special_functions/detail/bessel_jy_asym.hpp @@ -120,6 +120,24 @@ inline T asymptotic_bessel_j_large_x_2(T v, T x) } template <class T> +inline bool asymptotic_bessel_large_x_limit(int v, const T& x) +{ + BOOST_MATH_STD_USING + // + // Determines if x is large enough compared to v to take the asymptotic + // forms above. From A&S 9.2.28 we require: + // v < x * eps^1/8 + // and from A&S 9.2.29 we require: + // v^12/10 < 1.5 * x * eps^1/10 + // using the former seems to work OK in practice with broadly similar + // error rates either side of the divide for v < 10000. + // At double precision eps^1/8 ~= 0.01. + // + BOOST_ASSERT(v >= 0); + return (v ? v : 1) < x * 0.004f; +} + +template <class T> inline bool asymptotic_bessel_large_x_limit(const T& v, const T& x) { BOOST_MATH_STD_USING |