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mongo group query how to keep fields
...are accumulated/funneled/reduced) doesn't make so much sense even theoretically. However, sorting before hand is actually inefficient compared to sorting each group within themselves since sorting algorithms are more complex than O(n). I wish there would be better ways in MongoDB.
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Difference between __str__ and __repr__?
...e come right out and say it — I do not believe in debuggers. I don’t really know how to use any debugger, and have never used one seriously. Furthermore, I believe that the big fault in debuggers is their basic nature — most failures I debug happened a long long time ago, in a galaxy far far a...
How to make an OpenGL rendering context with transparent background?
Rendering contexts usually have a solid color on the background (black or whatever, see the image below):
9 Answers
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How do I install cygwin components from the command line?
... the Cygwin package similar to apt-get on Debian or yum on redhat that allows me to install components from the command line?
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Why does changing 0.1f to 0 slow down performance by 10x?
...ond run the numbers are very close to zero.
Denormalized numbers are generally rare and thus most processors don't try to handle them efficiently.
To demonstrate that this has everything to do with denormalized numbers, if we flush denormals to zero by adding this to the start of the code:
_MM_...
Convert list to dictionary using linq and not worrying about duplicates
...t 2.0 framework at work... @onof Not exactly hard to ignore case. Just add all keys in uppercase.
– Carra
Jul 23 '10 at 14:42
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How to efficiently count the number of keys/properties of an object in JavaScript?
...t only iterates through the object but also creates a whole new array with all its keys, so it completely fails at answering the question.
– GetFree
Jun 22 '12 at 14:28
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Coalesce function for PHP?
...HP 7 introduced a real coalesce operator:
echo $_GET['doesNotExist'] ?? 'fallback'; // prints 'fallback'
If the value before the ?? does not exists or is null the value after the ?? is taken.
The improvement over the mentioned ?: operator is, that the ?? also handles undefined variables without...
Overriding superclass property with different type in Swift
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Swift does not allow you to change the class type of any variables or properties. Instead you can create an extra variable in the subclass that handles the new class type:
class Chassis {}
class RacingChassis : Chassis {}
class Car {
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Print multiple arguments in Python
...or", name, "is", score)
If you don't want spaces to be inserted automatically by print in the above example, change the sep parameter:
print("Total score for ", name, " is ", score, sep='')
If you're using Python 2, won't be able to use the last two because print isn't a function in Python 2. Y...