get_partial_softmax_reverse_right Function

  function get_partial_softmax_reverse_right(this, upstream_grad) result(output)
    !! Get partial derivative of softmax reverse operation
    implicit none
    class(array_type), intent(inout) :: this
    type(array_type), intent(in) :: upstream_grad
    type(array_type) :: output

    type(array_type), pointer :: ptr

    ptr => ( &
         upstream_grad - &
         sum(this%left_operand * upstream_grad, dim=this%indices(1)) &
    ) * this%left_operand
    call output%assign_and_deallocate_source(ptr)

  end function get_partial_softmax_reverse_right