static bool same_size( const vex::multivector< T , N , own > &x1 , const vex::multivector< T , N , own > &x2 )
 {
     return x1.size() == x2.size();
 }
 static void resize( vex::multivector< T , N , own > &x1 , const vex::multivector< T , N , own > &x2 )
 {
     x1.resize( x2.queue_list() , x2.size() );
 }