6 Tips to write BETTER For Loops in Python

for the iterator comprehension, you can get rod of those ugly indices with
study_times = (minutes for task, minutes in events if task == "learn")

You also won't make the error to use it twice if you put it directly in the sum call (makes more concise code, too):
minutes_studies = sum(minutes for task, minutes in events if task == "learn")

😢

Stick to the basics. Don't memorize useless stuffs.

Okay what is the vs code theme? Oh and good video, really helpful

isn’t an out of range array index supposed to return undefined?

very interesting the itertools packages, i didnt know about it.

It would be good to mention how much memory each method uses. I have seen some horrific python codes in memory requirements, compounded by the author having no idea why it uses as much memory as it does

7th tip: just use another language like C or Java

Why use islice(lines, 5) instead of lines[:5] ?

Great video. Very useful. Thanks

Syntax error on line 1 in thumbnail 🤓
Also nice vid

I learned a lot from this vid; learned even more from the comments 🐍 💬

Whatever man, I'm sticking with my 6 nested for loops. 🤌

clickbait

No idea about python but in every instance where a for in loop can be used it’s a lot more efficient to use a traditional for loop

The thumbnail is missing a bracket


You meant to do this instead:

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

step 1: ask chatGPT
step 2: copy
step 3: paste

What about recursion? p.s. It couldn’t be true that imperative language can't deal with loops or ? 🤔

ah this video too late.. my final project already done 🥲

Cool😊

What for should i use islice instead of [ : 5]?

Bad advise: "write more complex code, and another programmers will spend more and more time to understand your code".

Noting new, but for generator and pairwise I would unpack in for like:

minutes_studied = (minutes for event, minutes in events if event == "learn")

for pair0, pair1 in pairwise(...):

Anything is better than your thumbnail code because that doesn’t even run

“This is very error-prone”: why?

You know, I get all these "use native methods" things in Python, but at what point does Python become less readable because there are all these little native functions?

Wouldn't it be better to let an optimizer turn a for loop into a list comprehension? Just how, exactly, is a list comprehension always better than a for loop in terms of readability? Sure, it's better for speed, but is it better for readability?

It would be an error if Python got turned into APL (a fabulous, but write-only language).

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Fire is a good servant, but a bad master.

Let us have computer languages which serve us, rather than having us serve them.

Something I dealt with recently is where I wanted to loop through the lines of a text file, find the first occurrence of e.g. "hello", and then loop from that point onwards, to find the first occurrence of "random", and, only if we find "random", go back through the lines between that containing "hello" and that containing "random". Iterators make it hard to consume, and harder still to backtrack, things that are easy with C's for(i=1;i<10;i++) construct.

Another is where if an element of a sequence matches some pattern, you want to consume and process the next element of the sequence before the loop continues. (The latter is a case where you have to do for x in I := iter(something): ... y= next(I)

and so on.

It would be nice to see a video where you show genuine cases where you have to use the 'ugly' loop construct, and where things like sum and zip aren't any help.

i hate to be that guy. but it is impressive how bad python messed up how loops are implemented. when in other languages its just a goto. wonder why they did that. thank god for pypy.

Now sum() is better style than "for" anyway. But other than that, if these performance differences matter to you, don't use CPython. Use a python interpreter with a good JIT that can optimise away these differences rather than writing fine-tuned code for a slow interpreter.

Great video. Also for an old dog good as a reminder. np is a powerful tool (like pandas) but very annoying are their type differences, e.g. None, float, etc.

Welp, may as well write my loop code in C/C++ and import it in python.

Is islice() == [::]?

I'm thinking lazy, and didn't get a point of using "islice" instead of standart "print(line) for line in lines[1:5:2]" slicing.

Pairwise would've been really useful in an AoC problem lol

I really need to read up itertools and functools. There's so much obscure but handy stuff there

Abt the generator tip,

I'd argue it's better to put the generator comprehension inside the function that uses it.

1 reason is as you've shown, storing it in a variable gives the impression that it is reusable when in fact it may be exhausted in some other place.

Another is that I think it's very readable that way, e.g.
sum(
event[1]
for event in events
)

I find that it reads really well with other functions too, namely `any` and `all`, e.g.
all(
event[1] > 10
for event in events
)

It is not true, that loops are bad, as they are the place that JIT compilers can shine after all. It is all just about the python implementation

Thanks for the tips, but tell us, what's your VS Code theme?

Питон это жуткий ущербный язык.

not sure if youve seen, but sum() does weird things with floats. for example

my_list = [0.1, 0.1, 0.1, 0.1, 0.1, 0.1, 0.1, 0.1, 0.1, 0.1]
sum(my_list) = 0.9999999

if you use numpy, np.sum(my_list) = 1

Can avoid some headaches this way especially when dealing with predictions of propensity where 0.001 can matter.

would be interesting if u include benchmark number also. Performance is also vital role when we do refactoring code, besides readability. For me performance is number one becoze python it self already readable by nature.

Thanks for your sharing

You forgot range closing ')' in code in the thumbnail.

I also like shades of purple 💜

I’ll just keep it simple and use foreach(array $list as $key => &value); loop in php

I really don't get why people love python, I have to use it daily at work since our backend is in python, and I have zero fun using it, I feel the language is not helping me, it is in my way

Please tell me which plugin did you use in the design

vs code theme name ?

coding is one of the few activities where being lazy is actually helpful

Did not know about the strict parameter added to zip in Py3.10. Nice!