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Does MongoDB's $in clause guarantee order
...d index order as shown.
If you need to preserve this order, then you basically have two options.
So let's say that you were matching on the values of _id in your documents with an array that is going to be passed in to the $in as [ 4, 2, 8 ].
Approach using Aggregate
var list = [ 4, 2, 8 ];
...
Among $_REQUEST, $_GET and $_POST which one is the fastest?
...what my application should do (i.e. one or the other, but not both) : generally speaking :
You should use $_GET when someone is requesting data from your application.
And you should use $_POST when someone is pushing (inserting or updating ; or deleting) data to your application.
Either way, the...
How to list imported modules?
How to enumerate all imported modules?
9 Answers
9
...
How to implement an ordered, default dict? [duplicate]
...deredDict() and defaultdict() from collections in one object, which shall be an ordered, default dict .
Is this possible?
...
How do I filter query objects by date range in Django?
...year='2011',
date__month='01')
Edit
As Bernhard Vallant said, if you want a queryset which excludes the specified range ends you should consider his solution, which utilizes gt/lt (greater-than/less-than).
...
Differences between lodash and underscore [closed]
...h run in Node, Ringo, Rhino, Narwhal, PhantomJS, and browsers), better overall performance and optimizations for large arrays/object iteration, and more flexibility with custom builds and template pre-compilation utilities.
Because Lo-Dash is updated more frequently than Underscore, a lodash unders...
What is the difference between quiet NaN and signaling NaN?
...unit (FPU) or library if floating-point is implemented in software. A signalling NaN will produce a signal, usually in the form of exception from the FPU. Whether the exception is thrown depends on the state of the FPU.
C++11 adds a few language controls over the floating-point environment and pr...
Evaluating a mathematical expression in a string
...p://pyparsing.wikispaces.com/message/view/home/15549426
'''
__note__ = '''
All I've done is rewrap Paul McGuire's fourFn.py as a class, so I can use it
more easily in other places.
'''
class NumericStringParser(object):
'''
Most of this code comes from the fourFn.py pyparsing example
...
Is there a difference between “==” and “is”?
... a
True
In your case, the second test only works because Python caches small integer objects, which is an implementation detail. For larger integers, this does not work:
>>> 1000 is 10**3
False
>>> 1000 == 10**3
True
The same holds true for string literals:
>>> "a" i...
Do try/catch blocks hurt performance when exceptions are not thrown?
... {
Console.WriteLine(ex.ToString());
}
finally
{
d = Math.Sin(d);
}
}
w.Stop();
Console.Write(" try/catch/finally: ");
Console.WriteLine(w.ElapsedMilliseconds);
w.Reset();
d = 0;
w.Start();
for (int i = ...