Defined in header <valarray> | ||
---|---|---|
template< class T > std::valarray<T> pow( const std::valarray<T>& base, const std::valarray<T>& exp ); | (1) | |
template< class T > std::valarray<T> pow( const std::valarray<T>& base, const typename std::valarray<T>::value_type& vexp ); | (2) | |
template< class T > std::valarray<T> pow( const typename std::valarray<T>::value_type& vbase, const std::valarray<T>& exp ); | (3) |
Raises a value to a power.
base
raised to the power specified by the corresponding element from the numeric array exp
.The behavior is undefined if base.size() != exp.size()
.
base
raised to the power vexp
.vbase
raised to the power defined by the elements in the numeric array exp
.base | - | numeric array containing the values of the base |
exp | - | numeric array containing the values of the exponent |
vbase | - | a value defining the base |
vexp | - | a value defining the exponent |
A numeric array containing the results of exponentiation.
Unqualified function (pow
) is used to perform the computation. If such function is not available, std::pow
is used due to argument dependent lookup.
The function can be implemented with the return type different from std::valarray
. In this case, the replacement type has the following properties:
const
member functions of std::valarray
are provided. std::valarray
, std::slice_array
, std::gslice_array
, std::mask_array
and std::indirect_array
can be constructed from the replacement type. const std::valarray&
except begin()
and end()
(since C++11) should also accept the replacement type. const std::valarray&
should accept every combination of const std::valarray&
and the replacement type. The following behavior-changing defect reports were applied retroactively to previously published C++ standards.
DR | Applied to | Behavior as published | Correct behavior |
---|---|---|---|
LWG 3074 | C++98 | T is deduced from both the scalar and the valarray for (2-3), disallowing mixed-type calls | only deduce T from the valarray |
applies the function std::sqrt to each element of valarray (function template) |
|
(C++11)(C++11) | raises a number to the given power (xy) (function) |
complex power, one or both arguments may be a complex number (function template) |
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