torch_tensor_get_device_index Function

  function torch_tensor_get_device_index(self) result(device_index)
    use, intrinsic :: iso_c_binding, only : c_int
    class(torch_tensor), intent(in) :: self  !! Input tensor
    integer(c_int) :: device_index           !! Device index of tensor

    interface
      function torch_tensor_get_device_index_c(tensor) result(device_index) &
          bind(c, name = 'torch_tensor_get_device_index')
        use, intrinsic :: iso_c_binding, only : c_int, c_ptr
        implicit none
        type(c_ptr), value, intent(in) :: tensor
        integer(c_int) :: device_index
      end function torch_tensor_get_device_index_c
    end interface

    if (.not. c_associated(self%p)) then
      write(*,*) "Error :: tensor has not been constructed so its device index is unset"
      stop 1
    end if
    device_index = torch_tensor_get_device_index_c(self%p)
  end function torch_tensor_get_device_index