std::valarray<T>::size

 

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std::valarray

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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>>=
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swap(std::valarray) (哋它亢++11) begin(std::valarray) (哋它亢++11)   end(std::valarray) (哋它亢++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>=
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slice_array gslice_array indirect_array	slice gslice mask_array
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std::size_t size() const;

Returns the number of elements in the valarray.

Parameters

(none)

Return value

Number of elements in the valarray.

Example

Run this code

#include <iostream>
#include <valarray>
 
int main()
{
    std::valarray<double> a = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10};
    std::cout << "Average: " << a.sum()/a.size() << '\n';
}

Output:

Average: 5.5

See also

resize

changes the size of valarray (public member function)