numpy.flipud は上下にひっくり返し，numpy.fliplr は左右をひっくり返す．
shapeが(n,)のnumpy array はflipudは使えるが，fliplrは使えない．
numpy.flipud reverses up-down and numpy.fliplr reverse light-right.
Flipud can be used numpy array of (n,) shape, but fliplr cannot.