std::end(std::valarray)

 

C++

Compiler support

Freestanding and hosted

Language

Standard library

Standard library headers

Named requirements

Feature test macros(C++20)

Language support library

Concepts library(C++20)

Diagnostics library

Memory management library

Metaprogramming library(C++11)

General utilities library

Containers library

Iterators library

Ranges library(C++20)

Algorithms library

Strings library

Text processing library

Numerics library

Date and time library

Input/output library

Filesystem library(C++17)

Concurrency support library(C++11)

Execution control library(C++26)

Technical specifications

Symbols index

External libraries

 

Numerics library

Common mathematical functions
Mathematical special functions(C++17)
Mathematical constants(C++20)
Basic linear algebra algorithms(C++26)
Data-parallel types (SIMD)(C++26)
Floating-point environment(C++11)
Complex numbers
Numeric array (valarray)
Pseudo-random number generation
Bit manipulation(C++20)
Saturation arithmetic(C++26)
Factor operations
gcd (C++17)	lcm (C++17)
Interpolations
midpoint (C++20)	lerp (C++20)
Generic numeric operations
iota (C++11) ranges::iota (C++23) accumulate inner_product adjacent_difference    partial_sum	reduce (C++17) transform_reduce (C++17) inclusive_scan (C++17) exclusive_scan (C++17) transform_inclusive_scan (C++17) transform_exclusive_scan (C++17)
C-style checked integer arithmetic
ckd_add (C++26) ckd_sub (C++26)	ckd_mul (C++26)

 

std::valarray

Member functions
valarray::valarray valarray::~valarray valarray::operator= valarray::operator[] valarray::swap valarray::size valarray::resize valarray::sum valarray::min valarray::max valarray::shift valarray::cshift valarray::apply	valarray::operator+valarray::operator-valarray::operator~valarray::operator! valarray::operator+=valarray::operator-=valarray::operator*=valarray::operator/=valarray::operator%=valarray::operator&=valarray::operator|=valarray::operator^=valarray::operator<<=valarray::operator>>=
Non-member functions
swap(std::valarray) (C++11) begin(std::valarray) (C++11)   end(std::valarray) (C++11) abs exp log log10 pow sqrt sin cos tan asin acos atan atan2 sinh cosh tanh	operator*operator/operator%operator+operator-operator^operator&operator|operator<<operator>>operator&&operator|| operator==operator!=operator<operator>operator<=operator>=
Helper classes
slice_array gslice_array indirect_array	slice gslice mask_array
Deduction guides(C++17)

 

template<class T > /* see below */ end( valarray<T>& v );	(1)	(since C++11)
template<class T > /* see below */ end(const valarray<T>& v );	(2)	(since C++11)

The overload of std::end for valarray returns an iterator of unspecified type referring to the one past the last element in the numeric array.

1) The return type must

• meet the requirements of mutableLegacyRandomAccessIterator,

model contiguous_iterator,

(since C++20)

• have a member type value_type, which is T, and
• have a member type reference, which is T&.

2) The return type must

• meet the requirements of constantLegacyRandomAccessIterator,

model contiguous_iterator,

(since C++20)

• have a member type value_type, which is T, and
• have a member type reference, which is const T&.

The iterator returned from this function is invalidated when the member function resize() is called on v or when the lifetime of v ends, whichever comes first.

Parameters

v

-

a numeric array

Return value

Iterator to one past the last value in the numeric array.

Exceptions

May throw implementation-defined exceptions.

Notes

Unlike other functions that take std::valarray arguments, end() cannot accept the replacement types (such as the types produced by expression templates) that may be returned from expressions involving valarrays: std::end(v1 + v2) is not portable, std::end(std::valarray<T>(v1 + v2)) has to be used instead.

The intent of this function is to allow range for loops to work with valarrays, not to provide container semantics.

Example

Run this code

#include <algorithm>#include <iostream>#include <valarray>   int main(){conststd::valarray<char> va {'H', 'e', 'l', 'l', 'o', ',', ' ', 'C', '+', '+', '!', '\n'};   std::for_each(std::begin(va), std::end(va), [](char c){std::cout<< c;});}

Output:

Hello, C++!

Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

DR	Applied to	Behavior as published	Correct behavior
LWG 2058	C++11	1. end() was required to support replacement types 2. it was unspecified when the returned iterators will be invalidated	1. not required 2. specified

See also

std::begin(std::valarray) (C++11)

overloads std::begin (function template)