slice notation python code example
Example 1: python array index range
a[start:stop] # items start through stop-1
a[start:] # items start through the rest of the array
a[:stop] # items from the beginning through stop-1
a[:] # a copy of the whole array
Example 2: slicing in python list
a = [1,2,3,4,5]
a[m:n] # elements grrater than equal to m and less than n
a[1:3] = [2,3]
Example 3: is : and :: the same in python slice
a[-1] # last item in the array
a[-2:] # last two items in the array
a[:-2] # everything except the last two items
Example 4: python list slice sybtax
# [start:stop:step]
# for example ...
l = [1, 2, 3, 4, 5]
l[1:4] # elements from 1 (inclusive) to 4 (exclusive)
l[2:5:2] # elements from 2 (inclusive) to 5 (exclusive) going up by 2