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How does MongoDB sort records when no sort order is specified?
When we run a Mongo find() query without any sort order specified, what does the database internally use to sort the results?
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What is “thread local storage” in Python, and why do I need it?
In Python specifically, how do variables get shared between threads?
5 Answers
5
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Remove querystring from URL
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Marginal optimisation if it matters (probably not): split('?', 1)[0].
– bobince
Mar 29 '10 at 22:56
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pyplot axes labels for subplots
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ax.grid(False) or plt.grid(False) is also needed if the global plotting parameters include a (visible) grid.
– Næreen
Oct 17 '17 at 17:31
3
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Get statistics for each group (such as count, mean, etc) using pandas GroupBy?
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Please see my answer if you want to get only one count column per group.
– Pedro M Duarte
Sep 26 '15 at 19:43
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Creating a dictionary from a csv file?
...r rows longer than expected; but shouldn't he be raising his own exception if there are too many items in a row? I would think that would mean there's an error with his input data.
– machine yearning
Jul 19 '11 at 1:22
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How to find all occurrences of a substring?
...t() for m in re.finditer('test', 'test test test test')]
#[0, 5, 10, 15]
If you want to find overlapping matches, lookahead will do that:
[m.start() for m in re.finditer('(?=tt)', 'ttt')]
#[0, 1]
If you want a reverse find-all without overlaps, you can combine positive and negative lookahead in...
Switch statement fall-through…should it be allowed? [closed]
... case 4:
case 6:
case 8:
result = EVEN_DIGIT;
break;
}
But if you have a case label followed by code that falls through to another case label, I'd pretty much always consider that evil. Perhaps moving the common code to a function and calling from both places would be a better idea....
In Typescript, How to check if a string is Numeric
...) // 1234
Number('9BX9') // NaN
You can also use the unary plus operator if you like shorthand:
+'1234' // 1234
+'9BX9' // NaN
Be careful when checking against NaN (the operator === and !== don't work as expected with NaN). Use:
isNaN(maybeNumber) // returns true if NaN, otherwise false
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How should one use std::optional?
... //try to parse an int from the given string,
//and return "nothing" if you fail
}
The same thing might be accomplished with a reference argument instead (as in the following signature), but using std::optional makes the signature and usage nicer.
bool try_parse_int(std::string s, int& ...