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How do I perform the SQL Join equivalent in MongoDB?
...ttps://docs.mongodb.org/master/reference/operator/aggregation/lookup/#pipe._S_lookup
From the docs:
{
$lookup:
{
from: <collection to join>,
localField: <field from the input documents>,
foreignField: <field from the documents of the "from" collection>...
Why does Python use 'magic methods'?
...
answered Apr 17 '10 at 7:32
Eli BenderskyEli Bendersky
218k7777 gold badges324324 silver badges390390 bronze badges
...
How can I convert string date to NSDate?
... */
let date = dateFormatter.dateFromString(/* your_date_string */)
For further query, check NSDateFormatter and DateFormatter classes of Foundation framework for Objective-C and Swift, respectively.
Swift 3 and later (Swift 4 included)
let dateFormatter = DateFormatter()...
Why does C++11 not support designated initializer lists as C99? [closed]
...kery, so just sharing for fun.
#define with(T, ...)\
([&]{ T ${}; __VA_ARGS__; return $; }())
And use it like:
MyFunction(with(Params,
$.Name = "Foo Bar",
$.Age = 18
));
which expands to:
MyFunction(([&] {
Params ${};
$.Name = "Foo Bar", $.Age = 18;
return $;
}()));
...
How to profile a bash shell script slow startup?
...
132
If you have GNU date (or another version that can output nanoseconds), do this at the beginning...
Avoid browser popup blockers
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answered Apr 6 '10 at 19:32
dthorpedthorpe
33k33 gold badges6969 silver badges114114 bronze badges
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How to use int.TryParse with nullable int? [duplicate]
...uld never copy/paste from the internet just because an answer is accepted ^_^.
– Thomas Jones
Jan 15 '15 at 22:59
17
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What does numpy.random.seed(0) do?
...
If you set the np.random.seed(a_fixed_number) every time you call the numpy's other random function, the result will be the same:
>>> import numpy as np
>>> np.random.seed(0)
>>> perm = np.random.permutation(10)
>>> p...
Python class inherits object
...ss ClassicSpam: # no base class
... pass
>>> ClassicSpam.__bases__
()
"new" style classes: they have, directly or indirectly (e.g inherit from a built-in type), object as a base class:
>>> class NewSpam(object): # directly inherit from object
... pass
>&g...
Default function arguments in Rust
...you can get a similar behavior using Option<T>
fn add(a: Option<i32>, b: Option<i32>) -> i32 {
a.unwrap_or(1) + b.unwrap_or(2)
}
This accomplishes the objective of having the default value and the function coded only once (instead of in every call), but is of course a who...