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What does “while True” mean in Python?
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while True means loop forever. The while statement takes an expression and executes the loop body while the expression evaluates to (boolean) "true". True always evaluates to boolean "true" and thus executes the loop body indefinitely. It's an idiom that you'll just get used to eventually! Most ...
How to test an SQL Update statement before running it?
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In addition to using a transaction as Imad has said (which should be mandatory anyway) you can also do a sanity check which rows are affected by running a select using the same WHERE clause as the UPDATE.
So if you UPDATE is
UPDATE foo
SET bar = 42
WHERE col1 = 1
AND col2 = 'foobar';
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How do I associate a Vagrant project directory with an existing VirtualBox VM?
...irtualBox VM, so that when I vagrant up Vagrant will import the base-box and create a new virtual machine.
10 Answers
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Why are properties without a setter not serialized
I have a serializable class and one of the properties in my class generates a Guid in the getter. The property implements no setter and is ignores during serialization. Why is that and do I always have to implement a setter in order for my property to be serialized.
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How to add dividers and spaces between items in RecyclerView?
...uld have been done previously in the ListView class, using the divider and dividerHeight parameters:
41 Answers
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How to read a line from the console in C?
... line in a C console program
The text entered might have a variable length and we can't make any assumption about its content.
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How to get .app file of a xcode application
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Build a release version, and the .app file is under build/Release folder of your project. Just copy it to Applications folder of your friend's machine. I don't think you need to build a installer.
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How do I encode and decode a base64 string?
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Null checks for input strings in both functions and the solution is perfect :)
– Sverrir Sigmundarson
Mar 29 '14 at 23:05
24
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How to check if a variable is an integer in JavaScript?
How do I check if a variable is an integer in JavaScript, and throw an alert if it isn't? I tried this, but it doesn't work:
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How to normalize a NumPy array to within a certain range?
...io /= np.max(np.abs(audio),axis=0)
image *= (255.0/image.max())
Using /= and *= allows you to eliminate an intermediate temporary array, thus saving some memory. Multiplication is less expensive than division, so
image *= 255.0/image.max() # Uses 1 division and image.size multiplications
i...