std::slice_array<T>::operator=

 

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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)

 

std::slice_array

Member functions

slice_array::slice_array

slice_array::~slice_array

slice_array::operator=

slice_array::operator+=slice_array::operator-=slice_array::operator*=slice_array::operator/=slice_array::operator%=slice_array::operator&=slice_array::operator|=slice_array::operator^=slice_array::operator<<=slice_array::operator>>=

 

void operator=( const T& value ) const;	(1)
void operator=( const std::valarray<T>& val_arr ) const;	(2)
const slice_array& operator=( const slice_array& other_arr ) const;	(3)

Assigns values to all referred elements.

1) Assigns value to all of the elements.

2) Assigns the elements of val_arr to the referred to elements of *this.

3) Assigns the selected elements from other_arr to the referred to elements of *this.

Parameters

value	-	a value to assign to all of the referred elements
val_arr	-	std::valarray to assign
other_arr	-	std::slice_array to assign

Return value

1,2) (none)

3) *this

Example

Run this code

#include <iostream>
#include <valarray>
 
void print(char const* remark, std::valarray<int> const& v = {})
{
    std::cout << remark;
    if (v.size() != 0)
    {
        std::cout << ':';
        for (int e : v)
            std::cout << ' ' << e;
    }
    std::cout << '\n';
}
 
int main()
{
    std::valarray<int> v1{1, 2, 3, 4, 5, 6, 7, 8};
    std::slice_array<int> s1 = v1[std::slice(1, 4, 2)];
    print("v1", v1);
    print("s1", s1);
 
    print("\n(1) operator=( const T& )");
    print("s1 = 42");
    s1 = 42; // (1)
    print("s1", s1);
    print("v1", v1);
 
    print("\n(2) operator=( const std::valarray<T>& )");
    std::valarray<int> v2{10, 11, 12, 13, 14, 15};
    print("v2", v2);
    print("s1 = v2");
    s1 = v2; // (2)
    print("s1", s1);
    print("v1", v1);
 
    print("\n(3) operator=( const slice_array& )");
    v1 = {1, 2, 3, 4, 5, 6, 7, 8};
    std::slice_array<int> s2 = v1[std::slice(0, 4, 1)];
    std::slice_array<int> s3 = v2[std::slice(1, 4, 1)];
    print("v1", v1);
    print("v2", v2);
    print("s2", s2);
    print("s3", s3);
    print("s2 = s3");
    s2 = s3; // (3) Note: LHS and RHS must have same size.
    print("s2", s2);
    print("v1", v1);
}

Output:

v1: 1 2 3 4 5 6 7 8
s1: 2 4 6 8
 
(1) operator=( const T& )
s1 = 42
s1: 42 42 42 42
v1: 1 42 3 42 5 42 7 42
 
(2) operator=( const std::valarray<T>& )
v2: 10 11 12 13 14 15
s1 = v2
s1: 10 11 12 13
v1: 1 10 3 11 5 12 7 13
 
(3) operator=( const slice_array& )
v1: 1 2 3 4 5 6 7 8
v2: 10 11 12 13 14 15
s2: 1 2 3 4
s3: 11 12 13 14
s2 = s3
s2: 11 12 13 14
v1: 11 12 13 14 5 6 7 8

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 123	C++98	overload (2) was non-const	made const
LWG 253	C++98	the copy assignment operator was private	made public
LWG 621	C++98	the copy assignment operator was non-const	made const