# Basic functions

xtensor provides the following basic functions for xexpressions and scalars:

Defined in `xtensor/xmath.hpp`

template<class E>
inline auto xt::abs(E &&e) noexcept -> detail::xfunction_type_t<math::abs_fun, E>

Absolute value function.

Returns an xfunction for the element-wise absolute value of e.

Parameters:

e – an xexpression

Returns:
template<class E>
inline auto xt::fabs(E &&e) noexcept -> detail::xfunction_type_t<math::fabs_fun, E>

Absolute value function.

Returns an xfunction for the element-wise absolute value of e.

Parameters:

e – an xexpression

Returns:
template<class E1, class E2>
inline auto xt::fmod(E1 &&e1, E2 &&e2) noexcept -> detail::xfunction_type_t<math::fmod_fun, E1, E2>

Remainder of the floating point division operation.

Returns an xfunction for the element-wise remainder of the floating point division operation e1 / e2.

Note

e1 and e2 can’t be both scalars.

Parameters:
Returns:
template<class E1, class E2>
inline auto xt::remainder(E1 &&e1, E2 &&e2) noexcept -> detail::xfunction_type_t<math::remainder_fun, E1, E2>

Signed remainder of the division operation.

Returns an xfunction for the element-wise signed remainder of the floating point division operation e1 / e2.

Note

e1 and e2 can’t be both scalars.

Parameters:
Returns:
template<class E1, class E2, class E3>
inline auto xt::fma(E1 &&e1, E2 &&e2, E3 &&e3) noexcept -> detail::xfunction_type_t<math::fma_fun, E1, E2, E3>

Returns an xfunction for e1 * e2 + e3 as if to infinite precision and rounded only once to fit the result type.

Note

e1, e2 and e3 can’t be scalars every three.

Parameters:
Returns:
template<class E1, class E2>
inline auto xt::maximum(E1 &&e1, E2 &&e2) noexcept -> detail::xfunction_type_t<math::maximum<void>, E1, E2>

Elementwise maximum.

Returns an xfunction for the element-wise maximum between e1 and e2.

Parameters:
Returns:
template<class E1, class E2>
inline auto xt::minimum(E1 &&e1, E2 &&e2) noexcept -> detail::xfunction_type_t<math::minimum<void>, E1, E2>

Elementwise minimum.

Returns an xfunction for the element-wise minimum between e1 and e2.

Parameters:
Returns:
template<class E1, class E2>
inline auto xt::fmax(E1 &&e1, E2 &&e2) noexcept -> detail::xfunction_type_t<math::fmax_fun, E1, E2>

Maximum function.

Returns an xfunction for the element-wise maximum of e1 and e2.

Note

e1 and e2 can’t be both scalars.

Parameters:
Returns:
template<class E1, class E2>
inline auto xt::fmin(E1 &&e1, E2 &&e2) noexcept -> detail::xfunction_type_t<math::fmin_fun, E1, E2>

Minimum function.

Returns an xfunction for the element-wise minimum of e1 and e2.

Note

e1 and e2 can’t be both scalars.

Parameters:
Returns:
template<class E1, class E2>
inline auto xt::fdim(E1 &&e1, E2 &&e2) noexcept -> detail::xfunction_type_t<math::fdim_fun, E1, E2>

Positive difference function.

Returns an xfunction for the element-wise positive difference of e1 and e2.

Note

e1 and e2 can’t be both scalars.

Parameters:
Returns:
template<class E1, class E2, class E3>
inline auto xt::clip(E1 &&e1, E2 &&lo, E3 &&hi) noexcept -> detail::xfunction_type_t<math::clamp_fun, E1, E2, E3>

Clip values between hi and lo.

Returns an xfunction for the element-wise clipped values between lo and hi

Parameters:
• e1 – an xexpression or a scalar

• lo – a scalar

• hi – a scalar

Returns:
template<class E>
inline auto xt::sign(E &&e) noexcept -> detail::xfunction_type_t<math::sign_fun, E>

Returns an element-wise indication of the sign of a number.

If the number is positive, returns +1. If negative, -1. If the number is zero, returns 0.

Parameters:

e – an xexpression

Returns: