BOOST_FORCEINLINE typename Target::type
operator()(Pos const& p, Size const&sz, Target const&) const
{
typedef typename Target::type type;
typedef typename meta::as_index<type>::type i_t;
return splat<type>( as_subscript(sz,enumerate<i_t>(p))[0] );
}
BOOST_FORCEINLINE typename Target::type
operator()(Pos const&p , Size const& sz, Target const& ) const
{
typedef typename Target::type type;
typedef typename meta::as_index<type>::type i_t;
typedef typename meta::
call<nt2::tag::enumerate_(Pos,meta::as_<i_t>)>::type p_t;
typedef typename nt2::result_of::as_subscript<Size,p_t>::type s_t;
// Retrieve 2D position from the linear index
s_t const pos = as_subscript(sz,nt2::enumerate<i_t>(p));
// Return a diagonal of val_
return nt2::if_else_zero(nt2::eq(pos[0],pos[1]), splat<type>(val_));
}
BOOST_FORCEINLINE
result_type operator()(A0 const& a0, A1 ind, A2 dim) const
{
std::size_t along = dim-1;
typename A0::extent_type ex1 = a0.extent();
ex1[along] = 1;
return boost::proto::make_expr< nt2::tag::line_
, container::domain
> ( boost::cref(a0)
, along
, as_index( a0.extent()
, as_subscript(ex1, ind)
)
, nt2::linesstride(a0, dim)
);
}
BOOST_FORCEINLINE typename Target::type
operator()(Pos const& p, Size const& sz, Target const&) const
{
typedef typename Target::type type;
typedef typename meta::as_index<type>::type i_t;
typedef typename meta::call<tag::enumerate_(Pos,meta::as_<i_t>)>::type p_t;
typedef typename nt2::result_of::as_subscript<Size,p_t>::type s_t;
typedef typename s_t::value_type v_t;
// Retrieve 2D position from the linear index
s_t const pos = as_subscript(sz,nt2::enumerate<i_t>(p));
// Return a 1 where it belongs
BOOST_AUTO_TPL(ii, nt2::splat<v_t>(i_));
BOOST_AUTO_TPL(jj, nt2::splat<v_t>(j_));
return nt2::if_else(nt2::logical_and(nt2::eq(pos[0],ii),
nt2::eq(pos[1],jj)),
nt2::One<type>(), nt2::Zero<type>());
}
