copysign() [2/3]

template<typename T , typename U >

T stan::math::copysign ( const T &  x, const U &  y  )

inline

Return the negation of the first argument if the first and second argument have different signs, otherwise return a copy of the first argument.

For the sake of this function, zero is considered positive. This function uses negation rather than literally copying signs to preserve derivatives.

Overload of std::copysign from cmath for argument-dependent lookup.

Template Parameters

T	type of first argument
U	type of second argument

Parameters

[in]	x	first complex argument
[in]	y	second complex argument

Returns

copy of the first argument, negated if necessary to match the sign of the second argument

Definition at line 30 of file copysign.hpp.