Map() Is More Powerful Than You THOUGHT In Python

Map() is more powerful than you thought in Python. #Python #Code #Shorts

[chidvilaskarpenahalli]

map() is not used often because we can easily do the same thing with a list comprehension

[MD-vsff]

Every part of my strong-type-loving brain just screams in agony seeing a string multiplied by a number like that.

[emrecrakoglu]

here is simpler version
values = [1, 2, 3, 4]
print([i*'x' for i in values])

[nothiiiiiiiing]

Before I knew list comprehensions I did some devious nested map functions

[TheLogicalHuman]

For any who's wondering why use this over list comprehension?

You must use map when you know you're using this function a lot.
You can save time by not write a lengthy unreadable comprehension syntax line.
Imagine a function had to be called a 100 times in total, map is better than writing 100 list comprehensions.

Only overhead is converting to list.

[bettercalldelta]

This is a great feature but I believe this is not the best example because a list comprehension would work better here.

Here's an actually good example:

inp = input("Enter numbers separated by space: ")
numbers = list(map(int, inp.split()))

[david_lev]

Why not just `(func(i) for i in iterable)`?
The same also with filter: `(x for x in iterable if func(x))`
The only gain is the use of lambda which can also be used but it is required to create the lambda object every time: `(x for x in iterable if (lambda _: True)(x))`

[josefkaras]

Just use list/generator comprehesion, it will be more redable

[sergioamador]

Why not use a generator expression or list comprehension instead?

[jimparsons]

For those that are interested, there are 'cheat sheets' for a number of programming languages, pdf form and just right for printing out, on line. Just Google your request.

[hidude]

A lot of people pointing out list comprehension instead: yes, in most cases that is fine esp if you are doing list(map(....)), but in some cases you dont need the temporary list made in memory and instead using generators is faster.

[elijahsagaran]

learned map in racket, cool to know that python has a similar function

[etaizilberman]

[I*'x' For i in values] should be both more efficient and faster to writr

[speakingsarcasm]

You can alternate use a generator...

mapped = (str(i) for i in values)

[notyouraveragepotato]

How you do the arrow?? And what does it actually signify??

[peterbarraud]

This can be done in one line using list comprehension.
Sorry, but I've never found a use for the map function, that can't be done using comprehensions

[lvmbk]

Probably I'm getting this wrong, but I think any language ahas such a map function if somebody writes it and then you import....

[oida]

Note that you should convert to a list you store the refrence somewhere when you want to use it more then once.
u=map(lambda n:10*n, range(1, 4))
print(list(u))
print(list(u))
gives:
[10, 20, 30]
[]

[KalebARoberts]

Why not just use a list comprehension?

[Darakon]

Here's another 'trick':
_ = *map(print, my_list),