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How come an array's address is equal to its value in C?
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The name of an array usually evaluates to the address of the first element of the array, so array and &array have the same value (but different types, so array+1 and &array+1 will not be equal if the array is more than 1 element long).
Ther...
How to create a unique index on a NULL column?
...rver 2005. I want to constrain the values in a column to be unique, while allowing NULLS.
4 Answers
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E731 do not assign a lambda expression, use a def
...rst form means that the name of the resulting
function object is specifically 'f' instead of the generic '<lambda>'.
This is more useful for tracebacks and string representations in
general. The use of the assignment statement eliminates the sole
benefit a lambda expression can offer o...
Convert a Python list with strings all to lowercase or uppercase
...ariable that contains strings. Is there a python function that can convert all the strings in one pass to lowercase and vice versa, uppercase?
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One line if statement not working
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@JayKilleen You're correct. Ruby is all about clever tricks, but it's that clever (:
– Nikita Rybak
Jan 23 '15 at 7:47
3
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Append a NumPy array to a NumPy array
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Well, the error message says it all: NumPy arrays do not have an append() method. There's a free function numpy.append() however:
numpy.append(M, a)
This will create a new array instead of mutating M in place. Note that using numpy.append() involves c...
Difference between a virtual function and a pure virtual function [duplicate]
... class. Derived classes can override virtual functions. Virtual functions called through base class pointers/references will be resolved at run-time. That is, the dynamic type of the object is used instead of its static type:
Derived d;
Base& rb = d;
// if Base::f() is virtual and Derived o...
How to securely store access token and secret in Android?
...other apps cannot access them. On a rooted devices, if the user explicitly allows access to some app that is trying to read them, the app might be able to use them, but you cannot protect against that. As for encryption, you have to either require the user to enter the decrypt passphrase every time ...
Android emulator-5554 offline
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In such a case, you can do all of the following in order to be assured that your emulator starts working again :
Go to cmd and type adb kill-server
Go to task manager and find adb in processes. If you find one, right click on it and click on end proc...
HEAD and ORIG_HEAD in Git
..., and it is a commit on top of which "git commit" would make a new one. Usually HEAD is symbolic reference to some other named branch; this branch is currently checked out branch, or current branch. HEAD can also point directly to a commit; this state is called "detached HEAD", and can be understood...