cos_pi powm1 sin_pi sqrt1pm1

sqrt1pm1() def sqrt1pm1 ( x  ) sqrt(1 + x) - 1 Purpose sqrt1pm1 evaluates sqrt(1 + x) - 1 accurately in the sense of relative error when x is very small. Returns float sqrt(1 + x) - 1. Parameters [in] x Argument x. (x >= -1) Error handling If x < -1, domain error (EDOM) occurs. Other range error (ERANGE) may occur. Reference boost/math/special_functions