valarray header
From Cppwiki
valarray is a C++ Standard Library #include. It is responsible for defining std::valarray and related functionality.
Types defined by <valarray>
std::gslice std::gslice_array std::indirect_array std::mask_array std::slice std::slice_array std::valarray
Functions defined by <valarray>
abs, acos, asin, atan, atan2 cos, cosh, exp, log, log10, pow, sin, sinh, sqrt, tan, tanh,
++ Explicit type specializations defined by <valarray> ==
template std::valarray<bool> { ... };