Skip to content

2018-08-10 Python

Idiomatic Python

Idiomatic Python#

Here are a few things you can watch out for to improve how obvious and fast your code is. Often, people coming from other programming languages don’t take advantage of the Python way.

Looping#

colours = ['red', 'green', 'blue', 'orange']

for colour in colours:
    print(colour)

# Not

for i in range(len(colours)):
    print(colours[i])

Reversing a Loop#

for colour in reversed(colours):
    print(colour)

# Not

for i in range(len(colours) - 1, -1, -1):
    print(colours[i])

Using Indices#

Use enumerate

for i, colour in enumerate(colours):
    print(i, '-->', colour)

Looping over 2 collections#

Use zip

colours = ['red', 'green', 'blue', 'orange']
names = ['raymond', 'rachel', 'matthew']

for name, colour in zip(names, colours):
    print(name, colour)

The problem with zip is that it uses a lot of memory, so you can use izip instead.