Indexing and slicing

Gets one item, or a range of items, from a string or list by position.

Synopsis

items[index]
items[-1]
items[start:stop]
items[index] = value

Positions start at 0. A negative index counts from the end: -1 is the last item.

A slice [start:stop] takes the items from start up to, but not including, stop. Leave either out to go to the end.

You can change a list item with =, but not a character in a string.

Name	Meaning
`index`	A position, from `0` to `len(items) - 1`, or negative from the end.
`start, stop`	Where a slice begins and the position it stops before.

One item, or a new string or list for a slice.

word = "python"
print(word[0])
print(word[-1])
print(word[0:3])
print(word[2:])
nums = [10, 20, 30]
nums[1] = 25
print(nums)

It prints:

p
n
pyt
thon
[10, 25, 30]

word = "python"
print(word[6])

Python stops with:

IndexError: string index out of range

"python" has 6 letters at positions 0 to 5. The last one is word[5], or word[-1].