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Why is pow(a, d, n) so much faster than a**d % n?
...was taking so long (> 20 seconds) for midsize numbers (~7 digits). I eventually found the following line of code to be the source of the problem:
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Immutable vs Mutable types
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Almost, but not exactly. Technically, all variables are passed by reference in Python, but have a semantics more like pass by value in C. A counterexample to your analogy is if you do def f(my_list): my_list = [1, 2, 3]. With pass-by-reference in C, the val...
How does the vim “write with sudo” trick work?
Many of you have probably seen the command that allows you to write on a file that needs root permission, even when you forgot to open vim with sudo:
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What is the difference between String.Empty and “” (empty string)?
...ich makes string.Empty more efficient.
In version 2.0 and later of .NET, all occurrences of "" refer to the same string literal, which means "" is equivalent to .Empty, but still not as fast as .Length == 0.
.Length == 0 is the fastest option, but .Empty makes for slightly cleaner code.
See the ...
Check if my app has a new version on AppStore
I would like to manually check if there are new updates for my app while the user is in it, and prompt him to download the new version. Can I do this by checking the version of my app in the app store - programatically?
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How to create a new database after initally installing oracle database 11g Express Edition?
I have installed Oracle Database 11g Express Edition on my pc (windows 7)
and I have installed Oracle SQL Developer as well.
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Adding new column to existing DataFrame in Python pandas
... because if you have multiple rows, and you use the assignment, it assigns all rows of the new column with that value ( in your case e) which is usually undesirable.
– Paniz
Apr 27 '19 at 22:42
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Is there a NumPy function to return the first index of something in an array?
...:
itemindex = numpy.where(array==item)
The result is a tuple with first all the row indices, then all the column indices.
For example, if an array is two dimensions and it contained your item at two locations then
array[itemindex[0][0]][itemindex[1][0]]
would be equal to your item and so woul...
How to move all files including hidden files into parent directory via *
...e set of solutions on this in UNIX & Linux's answer to How do you move all files (including hidden) from one directory to another?. It shows solutions in Bash, zsh, ksh93, standard (POSIX) sh, etc.
You can use these two commands together:
mv /path/subfolder/* /path/ # your current approach...
How do I set the UI language in vim?
...my OS is set up in German (the standard at our office), I guess vim is actually trying to be helpfull.
15 Answers
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