operator+,-,*,/,%,&,|,^,<<,>>,&&,||(std::valarray)

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[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

*operatoroperator/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]

Defined in header`<valarray>`
template<class T> std::valarray<T> operator+(conststd::valarray<T>& lhs,conststd::valarray<T>& rhs); template<class T> std::valarray<T> operator-(conststd::valarray<T>& lhs,conststd::valarray<T>& rhs); template<class T> std::valarray<T> operator*(conststd::valarray<T>& lhs,conststd::valarray<T>& rhs); template<class T> std::valarray<T> operator/(conststd::valarray<T>& lhs,conststd::valarray<T>& rhs); template<class T> std::valarray<T> operator%(conststd::valarray<T>& lhs,conststd::valarray<T>& rhs); template<class T> std::valarray<T> operator&(conststd::valarray<T>& lhs,conststd::valarray<T>& rhs); template<class T> std::valarray<T> operator\|(conststd::valarray<T>& lhs,conststd::valarray<T>& rhs); template<class T> std::valarray<T> operator^(conststd::valarray<T>& lhs,conststd::valarray<T>& rhs); template<class T> std::valarray<T> operator<<(conststd::valarray<T>& lhs,conststd::valarray<T>& rhs); template<class T> std::valarray<T> operator>>(conststd::valarray<T>& lhs,conststd::valarray<T>& rhs); template<class T> std::valarray<bool> operator&&(conststd::valarray<T>& lhs,conststd::valarray<T>& rhs); template<class T> std::valarray<bool> operator\|\|(conststd::valarray<T>& lhs,conststd::valarray<T>& rhs);	(1)
template<class T> std::valarray<T> operator+(consttypenamestd::valarray<T>::value_type& val, conststd::valarray<T>& rhs); template<class T> std::valarray<T> operator-(consttypenamestd::valarray<T>::value_type& val, conststd::valarray<T>& rhs); template<class T> std::valarray<T> operator*(consttypenamestd::valarray<T>::value_type& val, conststd::valarray<T>& rhs); template<class T> std::valarray<T> operator/(consttypenamestd::valarray<T>::value_type& val, conststd::valarray<T>& rhs); template<class T> std::valarray<T> operator%(consttypenamestd::valarray<T>::value_type& val, conststd::valarray<T>& rhs); template<class T> std::valarray<T> operator&(consttypenamestd::valarray<T>::value_type& val, conststd::valarray<T>& rhs); template<class T> std::valarray<T> operator\|(consttypenamestd::valarray<T>::value_type& val, conststd::valarray<T>& rhs); template<class T> std::valarray<T> operator^(consttypenamestd::valarray<T>::value_type& val, conststd::valarray<T>& rhs); template<class T> std::valarray<T> operator<<(consttypenamestd::valarray<T>::value_type& val, conststd::valarray<T>& rhs); template<class T> std::valarray<T> operator>>(consttypenamestd::valarray<T>::value_type& val, conststd::valarray<T>& rhs); template<class T> std::valarray<bool> operator&&(consttypenamestd::valarray<T>::value_type& val, conststd::valarray<T>& rhs); template<class T> std::valarray<bool> operator\|\|(consttypenamestd::valarray<T>::value_type& val, conststd::valarray<T>& rhs);	(2)
template<class T> std::valarray<T> operator+(conststd::valarray<T>& lhs, consttypenamestd::valarray<T>::value_type& val); template<class T> std::valarray<T> operator-(conststd::valarray<T>& lhs, consttypenamestd::valarray<T>::value_type& val); template<class T> std::valarray<T> operator*(conststd::valarray<T>& lhs, consttypenamestd::valarray<T>::value_type& val); template<class T> std::valarray<T> operator/(conststd::valarray<T>& lhs, consttypenamestd::valarray<T>::value_type& val); template<class T> std::valarray<T> operator%(conststd::valarray<T>& lhs, consttypenamestd::valarray<T>::value_type& val); template<class T> std::valarray<T> operator&(conststd::valarray<T>& lhs, consttypenamestd::valarray<T>::value_type& val); template<class T> std::valarray<T> operator\|(conststd::valarray<T>& lhs, consttypenamestd::valarray<T>::value_type& val); template<class T> std::valarray<T> operator^(conststd::valarray<T>& lhs, consttypenamestd::valarray<T>::value_type& val); template<class T> std::valarray<T> operator<<(conststd::valarray<T>& lhs, consttypenamestd::valarray<T>::value_type& val); template<class T> std::valarray<T> operator>>(conststd::valarray<T>& lhs, consttypenamestd::valarray<T>::value_type& val); template<class T> std::valarray<bool> operator&&(conststd::valarray<T>& lhs, consttypenamestd::valarray<T>::value_type& val); template<class T> std::valarray<bool> operator\|\|(conststd::valarray<T>& lhs, consttypenamestd::valarray<T>::value_type& val);	(3)

Apply binary operators to each element of two valarrays, or a valarray and a value.

1) The operators works on valarrays of the same size and returns a valarray with the same size as the parameters with the operation applied to every elements of the two arguments.

2,3) Applies the operator between each element of the valarray and the scalar.

[edit]Parameters

rhs	-	a numeric array
lhs	-	a numeric array
val	-	a value of type`T`

[edit]Return value

A valarray with the same size as the parameter.

[edit]Note

The behaviour is undefined when the two arguments are valarrays with different sizes.

The function can be implemented with the return type different fromstd::valarray. In this case, the replacement type has the following properties:

Allconst member functions ofstd::valarray are provided.
std::valarray,std::slice_array,std::gslice_array,std::mask_array andstd::indirect_array can be constructed from the replacement type.
For every function taking aconststd::valarray<T>&exceptbegin() andend()(since C++11), identical functions taking the replacement types shall be added;
For every function taking twoconststd::valarray<T>& arguments, identical functions taking every combination ofconststd::valarray<T>& and replacement types shall be added.
The return type does not add more than two levels of template nesting over the most deeply-nested argument type.

[edit]Example

Finds real roots of multipleQuadratic equations.

Run this code

#include <cstddef>#include <iostream>#include <valarray> int main(){std::valarray<double> a(1,8);std::valarray<double> b{1,2,3,4,5,6,7,8};std::valarray<double> c=-b;// literals must also be of type T until LWG3074 (double in this case)std::valarray<double> d=std::sqrt(b* b-4.0* a* c);std::valarray<double> x1=2.0* c/(-b+ d);std::valarray<double> x2=2.0* c/(-b- d);std::cout<<"quadratic equation:  root 1:    root 2:   b: c:\n";for(std::size_t i=0; i< a.size();++i)std::cout<< a[i]<<"\u00B7x\u00B2 + "<< b[i]<<"\u00B7x + "<< c[i]<<" = 0  "<<std::fixed<< x1[i]<<"  "<< x2[i]<<std::defaultfloat<<"  "<<-x1[i]- x2[i]<<"  "<< x1[i]* x2[i]<<'\n';}

Output:

quadratic equation:  root 1:    root 2:   b: c:1·x² + 1·x + -1 = 0  -1.618034  0.618034  1  -11·x² + 2·x + -2 = 0  -2.732051  0.732051  2  -21·x² + 3·x + -3 = 0  -3.791288  0.791288  3  -31·x² + 4·x + -4 = 0  -4.828427  0.828427  4  -41·x² + 5·x + -5 = 0  -5.854102  0.854102  5  -51·x² + 6·x + -6 = 0  -6.872983  0.872983  6  -61·x² + 7·x + -7 = 0  -7.887482  0.887482  7  -71·x² + 8·x + -8 = 0  -8.898979  0.898979  8  -8

[edit]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 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`

[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>>=	applies compound assignment operator to each element of the valarray (public member function)[edit]