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Mongodb Explain for Aggregation framework
...ther manipulation will be in-memory (possibly using temporary files if the allowDiskUse option is set).
Optimizing pipelines
In general, you can optimize aggregation pipelines by:
Starting a pipeline with a $match stage to restrict processing to relevant documents.
Ensuring the initial $match / ...
How to delete (not cut) in Vim?
...
Use the "black hole register", "_ to really delete something: "_d.
Use "_dP to paste something and keep it available for further pasting.
For the second question, you could use <C-o>dw. <C-o> is used to execute a normal command without leaving ...
Swift - Split string over multiple lines
... some text
over multiple lines
"""
Older versions of Swift don't allow you to have a single literal over multiple lines but you can add literals together over multiple lines:
var text = "This is some text\n"
+ "over multiple lines\n"
...
Dictionaries and default values
...collections import defaultdict
a = defaultdict(lambda: "default", key="some_value")
a["blabla"] => "default"
a["key"] => "some_value"
You can pass any ordinary function instead of lambda:
from collections import defaultdict
def a():
return 4
b = defaultdict(a, key="some_value")
b['absent...
What is the best way to remove accents (normalize) in a Python unicode string?
I have a Unicode string in Python, and I would like to remove all the accents (diacritics).
8 Answers
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Why does “pip install” inside Python raise a SyntaxError?
...stalled package so this is the right way of using the API: subprocess.check_call([sys.executable, '-m', 'pip', 'install', 'SomeProject']) but since Python allows to access internal API and you know what you're using the API for you may want to use internal API anyway eg. if you're building own GUI p...
Adding custom radio buttons in android
... option ..... how to remove that ... keeping the functionality intact .... All i am trying to achieve as i showed in my question ... Any further directions ! [Note:: please look at the updated question]
– Devrath
Oct 3 '13 at 16:41
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Changing every value in a hash in Ruby
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@Andrew Marshall Right you are, thanks. In Ruby 1.8, Hash.[] doesn't accept an array of array pairs, it requires an even number of direct arguments (hence the splat up front).
– Phrogz
Mar 4 '11 at 3...
printf with std::string?
...f what it expects definitely won't give you the results you want. It's actually undefined behaviour, so anything at all could happen.
The easiest way to fix this, since you're using C++, is printing it normally with std::cout, since std::string supports that through operator overloading:
std::cout...
Position of least significant bit that is set
...is very slow compared to multiplication on modern hardware. So I wouldn't call it a better solution.
– Apriori
Mar 28 '14 at 1:37
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