/* * \file tnt_math_utils.h * \brief tnt_math_utils.h */ #ifndef IMPALGEBRA_TNT_MATH_UTILS_H #define IMPALGEBRA_TNT_MATH_UTILS_H /* needed for fabs, sqrt() below */ #include "../algebra_config.h" #include IMPALGEBRA_BEGIN_INTERNAL_NAMESPACE namespace TNT { using namespace std; /** @returns hypotenuse of real (non-complex) scalars a and b by avoiding underflow/overflow using (a * sqrt( 1 + (b/a) * (b/a))), rather than sqrt(a*a + b*b). */ template Real hypot(const Real &a, const Real &b) { if (a== 0) return abs(b); else { Real c = b/a; return fabs(a) * sqrt(1 + c*c); } } } /* TNT namespace */ IMPALGEBRA_END_INTERNAL_NAMESPACE #endif /* IMPALGEBRA_TNT_MATH_UTILS_H */