list[::], tuple[::] - extended slices

python - extended slices

python에서 list, tuple를 자를 때, 효과적인 방법

list[start index:end index+1:step]

>>> list_int = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]

# slice
>>> list_int[:2]
[0, 1]
>>> list_int[0:2]
[0, 1]
>>> list_int[:5]
[0, 1, 2, 3, 4]
>>> list_int[2:5]
[2, 3, 4]


>>> list_int[::1]
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
# even
>>> list_int[::2]
[0, 2, 4, 6, 8]
# odd
>>> list_int[1::2]
[1, 3, 5, 7, 9]
>>> list_int[::3]
[0, 3, 6, 9]

# reverse
>>> list_int[::-1]
[9, 8, 7, 6, 5, 4, 3, 2, 1, 0]
>>> list_int[::-2]
[9, 7, 5, 3, 1]