numpy.unique

python

>>> set(np.int64("1 2 3 1 4 2 0".split()))
{0, 1, 2, 3, 4}
>>> np.unique(np.int64("1 2 3 1 4 2 0".split()))
array([0, 1, 2, 3, 4])

setがハッシュテーブルであるのに対し、こちらはソート済みのnp.arrayである https://numpy.org/doc/stable/reference/generated/numpy.unique.html

numpy.searchsortedで二分探索できる

This function uses the same algorithm as the builtin python bisect.bisect_left (side=‘left’) and bisect.bisect_right (side=‘right’) functions, which is also vectorized in the v argument. https://numpy.org/doc/stable/reference/generated/numpy.searchsorted.html

numpy