Should You Use A List Or A Set? // Python Tips

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[vldor]

I think the uniqueness of set items should also be a factor here, it's probably the most important

[tamles]

You actually changed the behavior of the function! (Looks like you introduced a bug)
If your review string is "super cool bad bad bad movie", the first version returns False and the new one (with set) returns True
It's because in the first version each "bad" will be counted, and in the second version you only count DISTINCT words.
That's why even for super simple functions we need unit tests :p
By the way, I really enjoy the quality of your videos and this the very first time I find a bug in it (I watched them all haha)

[johnstoner]

You can write your set operators as symbols, so & instead of .intersection()...
Also you can treat dict keys as sets. This is great for stuff like validating json/yaml. Ala:

if valid_keys == input.keys(): if all should be there, or
if valid_keys - input.keys() == set() if you want to say the only keys you want is valid_keys.

[mrmivpushkin]

In my opinion you are using sets not to "make the code cleaner" but exactly because you need set operations like Union, Difference etc... In addition you would mainly use sets if you have unique elements and I don't care about the index of an element. It gives you the benefit of much faster "is in" operations compared to lists.

[DistortedV]

This is actually an overlooked gem. I think I've done the for x in..way too many times

[xlerb_again_to_music]

Also set lookup is fast vs. linearly scanning a list (esp. big lists) as set will use a form of hashing, like dicts.

[MrAjiii]

Love this and these shorts. Out of curiosity what's the space, time complexity compared to a for loop?

[Gummibandet]

I see why you need to consider the different data types for the appropriate application, but this wasn't a good example (when the main advantage mentioned was simpler/shorter code) because with list comprehension you could also do it in 2 rows.

[Ivan-Bagrintsev]

There is a set intersection operator &.
I believe that "a & b" looks much more simple (and clear) than "a.intersection(b)"

[alecclews]

The thing that bought home how important the right data structure was the backtracking solution to the 8 queen problem described by Horowitz and Sahni (Fundamentals of Computer Algorithms 1978 Page 337)

[Gokuroro]

cs]} to replace ] for } with vim bindings

[abilitytools]

For python 2.7.17 (obsolete) the line `def detect_positive(review: str) -> bool:` needs to say `def detect_positive(review=""): # -> bool` because python 2 raises `SyntaxError: invalid syntax`. The `list` vs. `set` discussion applies to both python 2 and 3.

[agastyam_]

If you're using a Vim emulation plugin, you could have used cs]} in order to change the surrounding square brackets into parentheses, instead of doing it manually :)

[ayder]

Maybe using the filter() function for the list, easier

[emiyox]

Fun fact, when iterating through a list to find if an item exists, it's generally more efficient to convert the list into a set and iterate through the set.

[oscarmartinezbeltran]

Short videos is a very stupid format even if the content is great