std::valarray<T>::operator+=,-=,*=,/=,%=,&=,|=,<<=,>>=

From cppreference.com

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

[edit]

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)

(C++17)

(C++17)

(C++20)

(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)

[edit]

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)

[edit]

valarray<T>& operator+=(const valarray<T>& v); valarray<T>& operator-=(const valarray<T>& v); valarray<T>& operator*=(const valarray<T>& v); valarray<T>& operator/=(const valarray<T>& v); valarray<T>& operator%=(const valarray<T>& v); valarray<T>& operator&=(const valarray<T>& v); valarray<T>& operator\|=(const valarray<T>& v); valarray<T>& operator^=(const valarray<T>& v); valarray<T>& operator<<=(const valarray<T>& v); valarray<T>& operator>>=(const valarray<T>& v);	(1)
valarray<T>& operator+=(const T& val); valarray<T>& operator-=(const T& val); valarray<T>& operator*=(const T& val); valarray<T>& operator/=(const T& val); valarray<T>& operator%=(const T& val); valarray<T>& operator&=(const T& val); valarray<T>& operator\|=(const T& val); valarray<T>& operator^=(const T& val); valarray<T>& operator<<=(const T& val); valarray<T>& operator>>=(const T& val);	(2)

Applies compound assignment operators to each element in the numeric array.

1) Each element is assigned value obtained by applying the corresponding operator to the previous value of the element and corresponding element fromv.

The behavior is undefined ifsize()!= v.size().

The behavior is undefined if any of the values inv is computed during the assignment and depends on any of the values in*this, that is, the expression on the right side of the assignment refers to a variable in the left side of the assignment.

2) Each element is assigned value obtained by applying the corresponding operator to the previous value of the element and the value ofval.

[edit]Parameters

v	-	another numeric array
val	-	a value

[edit]Return value

*this

[edit]Exceptions

May throw implementation-defined exceptions.

[edit]Notes

Each of the operators can only be instantiated if the following requirements are met:

The indicated operator can be applied to typeT.
The result value can be unambiguously converted toT.

[edit]Example

Run this code

#include <iostream>#include <string_view>#include <type_traits>#include <valarray> void o(std::string_view rem,autoconst& v,bool nl=false){ifconstexpr(std::is_scalar_v<std::decay_t<decltype(v)>>)std::cout<< rem<<" : "<< v;else{for(std::cout<< rem<<" : { ";autoconst e: v)std::cout<< e<<' ';std::cout<<'}';}std::cout<<(nl?"\n":";  ");} int main(){std::valarray<int> x, y;     o("x", x={1,2,3,4}), o("y", y={4,3,2,1}), o("x += y", x+= y,1);    o("x", x={4,3,2,1}), o("y", y={3,2,1,0}), o("x -= y", x-= y,1);    o("x", x={1,2,3,4}), o("y", y={5,4,3,2}), o("x *= y", x*= y,1);    o("x", x={1,3,4,7}), o("y", y={1,1,3,5}), o("x &= y", x&= y,1);    o("x", x={0,1,2,4}), o("y", y={4,3,2,1}), o("x <<=y", x<<=y,1); std::cout<<'\n';     o("x", x={1,2,3,4}), o("x += 5", x+=5,1);    o("x", x={1,2,3,4}), o("x *= 2", x*=2,1);    o("x", x={8,6,4,2}), o("x /= 2", x/=2,1);    o("x", x={8,4,2,1}), o("x >>=1", x>>=1,1);}

Output:

x : { 1 2 3 4 };  y : { 4 3 2 1 };  x += y : { 5 5 5 5 }x : { 4 3 2 1 };  y : { 3 2 1 0 };  x -= y : { 1 1 1 1 }x : { 1 2 3 4 };  y : { 5 4 3 2 };  x *= y : { 5 8 9 8 }x : { 1 3 4 7 };  y : { 1 1 3 5 };  x &= y : { 1 1 0 5 }x : { 0 1 2 4 };  y : { 4 3 2 1 };  x <<=y : { 0 8 8 8 } x : { 1 2 3 4 };  x += 5 : { 6 7 8 9 }x : { 1 2 3 4 };  x *= 2 : { 2 4 6 8 }x : { 8 6 4 2 };  x /= 2 : { 4 3 2 1 }x : { 8 4 2 1 };  x >>=1 : { 4 2 1 0 }

[edit]See also

operator+operator-operator~operator!	applies a unary arithmetic operator to each element of the valarray (public member function)[edit]
operator+operator-operator*operator/operator%operator&operator\|operator^operator<<operator>>operator&&operator\|\|	applies binary operators to each element of two valarrays, or a valarray and a value (function template)[edit]