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Why can I not push_back a unique_ptr into a vector?
...to a local variable. The lifetime of a local variable is managed automatically: local variables are destroyed when the block ends (e.g., when the function returns, in this case). You need to dynamically allocate the object:
std::unique_ptr<int> ptr(new int(1));
...
MongoDB/Mongoose querying at a specific date?
...onents. To query those times you need to create a date range that includes all moments in a day.
db.posts.find( //query today up to tonight
{"created_on": {"$gte": new Date(2012, 7, 14), "$lt": new Date(2012, 7, 15)}})
s...
What is the difference between ndarray and array in numpy?
...r are used.
If buffer is an object exposing the buffer interface, then all keywords are interpreted.
The example below gives a random array because we didn't assign buffer value:
np.ndarray(shape=(2,2), dtype=float, order='F', buffer=None)
array([[ -1.13698227e+002, 4.25087011e-303],
...
Counting the Number of keywords in a dictionary in python
... the len() function.
> a = {'foo':42, 'bar':69}
> len(a)
2
To get all the distinct words (i.e. the keys), use the .keys() method.
> list(a.keys())
['foo', 'bar']
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Matplotlib (pyplot) savefig outputs blank image
...values that depend whether or not T0 exists.
Second, after plt.show() is called, a new figure is created. To deal with this, you can
Call plt.savefig('tessstttyyy.png', dpi=100) before you call plt.show()
Save the figure before you show() by calling plt.gcf() for "get current figure", then you ca...
Is it better to call ToList() or ToArray() in LINQ queries?
...rray and growing the array until it fits them all.
If you desire concrete confirmation of this fact, check out the implementation of the methods in question in Reflector -- you'll see they boil down to almost identical code.
...
Batch file. Delete all files and folders in a directory
...e
echo.
echo Empties the contents of the specified directory,
echo WITHOUT CONFIRMATION. USE EXTREME CAUTION!
goto :DONE
:START
pushd %1 || goto :DONE
rd /q /s . 2> NUL
popd
:DONE
endlocal
The pushd changes into the directory of which you want to delete the children. Then when rd asks to dele...
XAMPP - MySQL shutdown unexpectedly
...
I confirm that deleting files will make all DB unusable. Table files are there but they can't display.
– Adrian P.
Apr 25 '18 at 0:27
...
How to make inline functions in C#
...=> x + y;
void print(int x) { Console.WriteLine(x); }
There are basically two different types for these: Func and Action. Funcs return values but Actions don't. The last type parameter of a Func is the return type; all the others are the parameter types.
There are similar types with different...
ReSharper warns: “Static field in generic type”
Is this wrong? I would assume that this actually has a static readonly field for each of the possible EnumRouteConstraint<T> that I happen to instance.
...