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Try-catch speeding up my code?
I wrote some code for testing the impact of try-catch, but seeing some surprising results.
5 Answers
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NTFS performance and large volumes of files and directories
...ry large when you have a lot of children. Note that it doesn't distinguish between a child that's a folder and a child that's a file. The only difference really is the content of that child is either the child's folder index or the child's file data. Note: I am simplifying this somewhat but this get...
How to randomize (or permute) a dataframe rowwise and columnwise?
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Given the R data.frame:
> df1
a b c
1 1 1 0
2 1 0 0
3 0 1 0
4 0 0 0
Shuffle row-wise:
> df2 <- df1[sample(nrow(df1)),]
> df2
a b c
3 0 1 0
4 0 0 0
2 1 0 0
1 1 1 0
By default sample() randomly reorders the elements passed as the first argumen...
How do I test a private function or a class that has private methods, fields or inner classes?
...vate methods, fields or nested classes? Or a function that is made private by having internal linkage ( static in C/C++) or is in a private ( anonymous ) namespace?
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How to randomly select an item from a list?
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Use random.choice()
import random
foo = ['a', 'b', 'c', 'd', 'e']
print(random.choice(foo))
For cryptographically secure random choices (e.g. for generating a passphrase from a wordlist) use secrets.choice()
import secrets
foo = ['battery', 'correct', 'horse', 'staple...
How to get the command line args passed to a running process on unix/linux systems?
...proc/<pid> on Linux, just have a look.
On other Unixes things might be different. The ps command will work everywhere, the /proc stuff is OS specific. For example on AIX there is no cmdline in /proc.
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Validating email addresses using jQuery and regex
...\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF]+)*|"((([ \t]*\r\n)?[ \t]+)?([\x01-\x08\x0b\x0c\x0e-\x1f\x7f\x21\x23-\x5b\x5d-\x7e\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF]|\\[\x01-\x09\x0b\x0c\x0d-\x7f\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF]))*(([ \t]*\r\n)?[ \t]+)?")@(([a-z\d\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF...
What does addChildViewController actually do?
...o do is implement a custom container view controller - lets call it SideBarViewController - that swaps out which of several possible child view controllers it shows, almost exactly like a standard Tab Bar Controller . (It's pretty much a Tab Bar Controller but with a hideable side menu instea...
Undefined reference to `pow' and `floor'
I'm trying to make a simple fibonacci calculator in C but when compiling gcc tells me that I'm missing the pow and floor functions. What's wrong?
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Bootstrap Dropdown menu is not working
I am having trouble getting my dropdowns to work. I can get the navbar to show up perfectly, but when I click on "Dropdown" (either of them) it does not display the dropdown menu. I have tried looking on other posts about this, but nothing that fixed everyone's problems helped. I copied the source s...