std::valarray<T>::size
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std::valarray 
std::size_t size() const;
 
 
Returns the number of elements in the valarray.
Contents
[edit] Parameters
(none)
[edit] Return value
Number of elements in the valarray.
[edit] 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