get_partial_outer_product_left Function

  function get_partial_outer_product_left(this, upstream_grad) result(output)
    implicit none
    class(array_type), intent(inout) :: this
    type(array_type), intent(in) :: upstream_grad
    type(array_type) :: output
    logical :: right_is_temporary_local
    type(array_type), pointer :: ptr

    right_is_temporary_local = this%right_operand%is_temporary
    this%right_operand%is_temporary = .false.
    if(this%is_forward)then
       ptr => upstream_grad .outer. this%right_operand
    else
       ptr => matmul(upstream_grad, this%right_operand)
    end if
    this%right_operand%is_temporary = right_is_temporary_local
    call output%assign_and_deallocate_source(ptr)
  end function get_partial_outer_product_left