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Random record from MongoDB
I am looking to get a random record from a huge (100 million record) mongodb .
26 Answers
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Getting the last element of a list
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some_list[-1] is the shortest and most Pythonic.
In fact, you can do much more with this syntax. The some_list[-n] syntax gets the nth-to-last element. So some_list[-1] gets the last element, some_list[-2] gets the second to last, etc, all the way down t...
Difference between >>> and >>
What is the difference between >>> and >> operators in Java?
7 Answers
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How do I get current date/time on the Windows command line in a suitable format for usage in a file/
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On my system %TIME% returns values like " 0:01:15" and " 3:15:12" and the %%a%%b code in the answer gives a leading space like " 001" and " 315". To get a four digit hhmm use this: For /f "tokens=1-2 delims=/: " %%a in ("%TIME%") do (if %%a LSS 10 (set mytime=0%%a%%b) else (s...
Given a number, find the next higher number which has the exact same set of digits as the original n
I just bombed an interview and made pretty much zero progress on my interview question. Can anyone let me know how to do this? I tried searching online but couldn't find anything:
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The located assembly's manifest definition does not match the assembly reference
...un some unit tests in a C# Windows Forms application (Visual Studio 2005), and I get the following error:
53 Answers
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How is this fibonacci-function memoized?
...mechanism in Haskell is by-need: when a value is needed, it is calculated, and kept ready in case it is asked for again. If we define some list, xs=[0..] and later ask for its 100th element, xs!!99, the 100th slot in the list gets "fleshed out", holding the number 99 now, ready for next access.
Th...
How to search by key=>value in a multidimensional array in PHP
..._r takes its fourth parameter by reference rather than by value; the ampersand & is crucial.
FYI: If you have an older version of PHP then you have to specify the pass-by-reference part in the call to search_r rather than in its declaration. That is, the last line becomes search_r($subarray, $k...
What is the difference between “JPG” / “JPEG” / “PNG” / “BMP” / “GIF” / “TIFF” Image?
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Yes. They are different file formats (and their file extensions).
Wikipedia entries for each of the formats will give you quite a bit of information:
JPEG (or JPG, for the file extension; Joint Photographic Experts Group)
PNG (Portable Network Graphics)
BMP (B...
How do I return multiple values from a function? [closed]
...ing library got the NamedTuple class to make named tuples easier to create and more powerful. Inheriting from typing.NamedTuple lets you use docstrings, default values, and type annotations.
Example (From the docs):
class Employee(NamedTuple): # inherit from typing.NamedTuple
name: str
id...