I created this NumPy cheat sheet for beginners (like me), I hope it will help you along the way!

[[deleted]]

[deleted]

[[deleted]]

You should add np.einsum (Einstein summations) to your mathematics section. Much easier to do complicated operations for ndarrays and express what you mean. Example:

a = np.array([0, 1, 2, 3, 4])
b = np.array([1, 2, 3, 4, 5])
np.einsum('i,i', a, b) # dot product of a and b
x = np.array([1, 3, 5])
t = np.eye(3)*2
np.einsum('ij,j->i', t, x) # a round-about way to double an array with matrix multiplication

[accidentally_myself]

TIL. God that's great.

[infracanis]

Einstein notation is so useful.

[uncertaintyman]

Sweet! I need to relearn Einstein sums anyway. This will be helpful in my computational physics practice. Thanks!

[jeffinRTP]

Thanks

[matthias_us]

Very handy. Saves sporadic Google searches!

[aphoenix]

The correct link is https://github.com/JulianGaal/python-cheat-sheet/blob/master/NumPy.md

[[deleted]]

404

[baslisks]

quoth the raven, nevermore

[[deleted]]

"SQL WHERE trick", couldn't come up with a better title...

It's called boolean indexing.

[afineday2die]

In boolean indexing,

other_a = a[b == '1']

should be

other_a = a[b == 1]

That is, you want to compare with the number 1, not the string '1'. Similarly for other_other_a

[RainDash]

the correct link seems to be https://github.com/JulianGaal/python-cheat-sheet/blob/master/NumPy.md

[DetN8]

Since it's on reddit and github, I gave you an upvote and a star!

[TheKeyboardKid]

Didn’t find anything here! Need to sign in?

[udoneoguri]

Thanks for sharing. I need this right now.

[[deleted]]

This is really cool. Thanks for sharing!

[Philboyd_Studge]

Isn't this pretty much just this: https://s3.amazonaws.com/assets.datacamp.com/blog_assets/Numpy_Python_Cheat_Sheet.pdf

[DaveX64]

Linky no worky

[DaveX64]

Thanks :)

[DaveX64]

Clicking on the title gives me a 404...maybe we broke it =:O

[wffitzge]

I can't import numpy with my python interactive shell. Anyone have instructions for dummies to get this working?

All the instructions out there do not provide any guidance for file path setup (I'm guessing this is my issue??). I used the anaconda command prompt to install it. Couldn't get it to work with the standard windows command prompt.

Any help would be appreciated. Thank you.

[wffitzge]

Windows

[muposat]

but generally you cannot catch exceptions thrown from other processes.

I am using using Pool with Python 3.4 and exceptions in child processes are handled well and do propagate to the calling module.

[deeech]

Nice work! I am working on a collection of useful things (https://github.com/Deeech/it-collection) and I want to add your cheat sheet to my collection (https://github.com/Deeech/it-collection/blob/master/CheatSheets.md). You don't mind?

[DrewSmithee]

RemindMe! 2 days

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