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) |
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(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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