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add a string prefix to each value in a string column using Pandas
...', 0]*200000})
%timeit df['col'].apply(lambda x: f"str{x}")
117 ms ± 451 µs per loop (mean ± std. dev. of 7 runs, 10 loops each)
%timeit 'str' + df['col'].astype(str)
112 ms ± 1.04 ms per loop (mean ± std. dev. of 7 runs, 10 loops each)
Using format, however, is indeed far slower:
%timeit ...
Is there a VB.NET equivalent for C#'s '??' operator?
Is there a VB.NET equivalent for C#'s ?? operator?
6 Answers
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Single Page Application: advantages and disadvantages [closed]
...t questions' searchability from a search engine).
– sçuçu
Apr 27 '16 at 17:15
5
Most SPA apps I...
Confused about Service vs Factory
...example. Do you know how i should annotate this?
– Pål
Oct 2 '14 at 13:56
2
Yes, there is there...
What are inline namespaces for?
...ames, while looking to users like the additional namespace doesn't exist⁽²⁾.
So, they're useful for splitting stuff into multiple sub-namespaces that all look like one namespace, if you need to do that for some reason. Of course, this is similar to writing using namespace inner in the outer na...
Is it possible dynamically to add String to String.xml in Android?
...
However, you should also read Elias Mårtenson's answer on Android plurals treatment of “zero”. There is a problem with the interpretation of certain values such as "zero".
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Should switch statements always contain a default clause?
... I have the same requirement where I work; we write code for embedded µControllers that have to pass strict safety checks and are often subjected to EMI. It would be irresponsible to assume that an enumerated variable will never have a value that is not in the enumeration list.
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Is “double hashing” a password less secure than just hashing it once?
...g users depends on your system.
You can probably let users wait an extra ¾ second or so during authentication. Profile your target platform, and use as many iterations as you can afford. Platforms I've tested (one user on a mobile device, or many users on a server platform) can comfortably suppor...
What does 'stale file handle' in Linux mean?
Say I have a terminal open, and through that terminal I have cd 'ed to some directory. Through another terminal, I delete that directory and restore it back from an identical backup. When I try to vim a file from the first terminal, in the same directory, why do I get an error about a stale file ...
What is bootstrapping?
I keep seeing "bootstrapping" mentioned in discussions of application development. It seems both widespread and important, but I've yet to come across even a poor explanation of what bootstrapping actually is; rather, it seems as though everyone is just supposed to know what it means. I don't, tho...