## ◆ group()

 downgrade_t boost::simd::group ( Value const & x, Value const & y )

This function object aggregates two boost::simd::pack of basic type T and cardinal N into a single boost::simd::pack of cardinal 2*N and using a type twice smaller than T.

Conversion of values during this operations are made using the C language conversion rules and may induce roll over.

For any type T and integral constant N, consider two value x and y of type boost::simd::pack<T,N>. The following code: