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Drop unused factor levels in a subsetted data frame
...tion, a new data frame is created. However, the factor variable retains all of its original levels, even when/if they do not exist in the new dataframe.
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How to set timeout on python's socket recv method?
...lect() to wait until data is available or until the timeout occurs. Only call recv() when data is actually available. To be safe, we also set the socket to non-blocking mode to guarantee that recv() will never block indefinitely. select() can also be used to wait on more than one socket at a time...
Xcode Command /usr/bin/codesign failed with exit code 1 : errSecInternalComponent
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Open Keychain Access, then in the File menu select Lock All Keychains.
Then go back to Xcode and clean and rebuild. It will prompt you for your password again to unlock the keychain.
After this, assuming you have no other compile issues, it will succeed!
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How to run Visual Studio post-build events for debug build only
...figuration)" == "Debug" worked for me. BTW, if you want to do something in all other configs, use if NOT "$(Configuration)" == "Debug".
– Ralf Hundewadt
Jun 29 '17 at 9:46
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Capturing Groups From a Grep RegEx
...egex="[0-9]+_([a-z]+)_[0-9a-z]*"
for f in $files # unquoted in order to allow the glob to expand
do
if [[ $f =~ $regex ]]
then
name="${BASH_REMATCH[1]}"
echo "${name}.jpg" # concatenate strings
name="${name}.jpg" # same thing stored in a variable
else
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“Keep Me Logged In” - the best approach
...e algorithm that you used. For example:
md5(salt+username+ip+salt)
Now, all an attacker needs to do is brute force the "salt" (which isn't really a salt, but more on that later), and he can now generate all the fake tokens he wants with any username for his IP address! But brute-forcing a salt is...
How do I get a consistent byte representation of strings in C# without manually specifying an encodi
How do I convert a string to a byte[] in .NET (C#) without manually specifying a specific encoding?
40 Answers
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Read String line by line
...s = myString.split(System.getProperty("line.separator"));
This gives you all lines in a handy array.
I don't know about the performance of split. It uses regular expressions.
share
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improve thi...
Where do you store your salt strings?
...ght about a salt per user I was thinking that a single salt would work for all users. What about a salt that is stored as an XML file that is loaded by the App Server? or maybe somehow hardcoded into a servlet?
– jigzat
Jul 25 '12 at 2:58
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What is an SDL renderer?
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SDL_Window
SDL_Window is the struct that holds all info about the Window itself: size, position, full screen, borders etc.
SDL_Renderer
SDL_Renderer is a struct that handles all rendering. It is tied to a SDL_Window so it can only render within that SDL_Window. It als...