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Python None comparison: should I use “is” or ==?
...n comparing arbitrary objects to singletons like None because it is faster and more predictable. is always compares by object identity, whereas what == will do depends on the exact type of the operands and even on their ordering.
This recommendation is supported by PEP 8, which explicitly states th...
How to prevent rm from reporting that a file was not found?
...errors. I do not need this message. I have searched the man page for a command to make rm quiet, but the only option I found is -f , which from the description, "ignore nonexistent files, never prompt", seems to be the right choice, but the name does not seem to fit, so I am concerned it might ha...
What to add for the update portion in ConcurrentDictionary AddOrUpdate
...f an update. I guess in your case (since you don't distinguish between add and update) this would be:
var sessionId = a.Session.SessionID.ToString();
userDic.AddOrUpdate(
authUser.UserId,
sessionId,
(key, oldValue) => sessionId);
I.e. the Func always returns the sessionId, so that both A...
Why is a “GRANT USAGE” created the first time I grant a user privileges?
I'm new to the admin side of DBMS and was setting up a new database tonight (using MySQL) when I noticed this. After granting a user a privilege for the first time, another grant is created that looks like
...
String to Dictionary in Python
So I've spent way to much time on this, and it seems to me like it should be a simple fix. I'm trying to use Facebook's Authentication to register users on my site, and I'm trying to do it server side. I've gotten to the point where I get my access token, and when I go to:
...
LINQ to Entities only supports casting EDM primitive or enumeration types with IEntity interface
... Perfect, it's great being able to perform Interface-based queries and still maintain the collection as IQueryable. A bit annoying however that there is basically no way of thinking up this fix, without knowing the inner workings of EF.
– Anders
Dec 9 '...
How to decompile an APK or DEX file on Android platform? [closed]
Is it possible to decompile an APK package or DEX file on Android platform?
Are there any tools that can decompile an APK file?
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Analyze audio using Fast Fourier Transform
...you need to calculate the square root of the sum of the square of its real and imaginary components. That is, if your coefficient is a + b*j, then its magnitude is sqrt(a^2 + b^2).
Once you have calculated the magnitude of each FFT coefficient, you need to figure out which audio frequency each FFT ...
Sourcetree - undo unpushed commits
I am using Sourcetree for Windows for a git-repository and would like to undo an unpushed commit.
4 Answers
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How to create a directory using nerdtree
... need to create a new directory I need to go to terminal. Is there a quick and easy way to create a directory using NERDTree.
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