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What is a WeakHashMap and when to use it? [duplicate]
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Here is a good sentence from that article: Weak references allow you to leverage the garbage collector's ability to determine reachability for you, so you don't have to do it yourself.
– Christophe Roussy
Jul ...
Inheritance and Overriding __init__ in python
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In each class that you need to inherit from, you can run a loop of each class that needs init'd upon initiation of the child class...an example that can copied might be better understood...
class Female_Grandparent:
def __init__(self):
self.grandma_na...
How to plot two columns of a pandas data frame using points?
I have a pandas data frame and would like to plot values from one column versus the values from another column. Fortunately, there is plot method associated with the data-frames that seems to do what I need:
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Why does flowing off the end of a non-void function without returning a value not produce a compiler
...eturn value could be set with embedded assembler or other tricky methods.
From C++11 draft:
§ 6.6.3/2
Flowing off the end of a function [...] results in undefined behavior in a value-returning function.
§ 3.6.1/5
If control reaches the end of main without encountering a return stateme...
How to make the 'cut' command treat same sequental delimiters as one?
I'm trying to extract a certain (the fourth) field from the column-based, 'space'-adjusted text stream. I'm trying to use the cut command in the following manner:
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Use different Python version with virtualenv
...on-config will be invoked with confusing consequences. See this bug report from 2011 github.com/pypa/virtualenv/issues/169 and my question stackoverflow.com/questions/42020937/…
– Laryx Decidua
Feb 23 '18 at 11:16
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Restore the state of std::cout after manipulating it
...cal variable and disable them before state.copyfmt, then restore exception from the variable (and do this again after restoring state from oldState which has exceptions disabled). 3) Set rdbuf to std::ios like this: struct : std::streambuf {} sbuf; std::ios oldState(&sbuf);
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Docker can't connect to docker daemon
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Linux
To run docker daemon on Linux (from CLI), run:
$ sudo service docker start # Ubuntu/Debian
Note: Skip the $ character when copy and pasting.
On RedHat/CentOS, run: sudo systemctl start docker.
To initialize the "base" filesystem, run:
$ sudo service ...
What does value & 0xff do in Java?
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It sets result to the (unsigned) value resulting from putting the 8 bits of value in the lowest 8 bits of result.
The reason something like this is necessary is that byte is a signed type in Java. If you just wrote:
int result = value;
then result would end up with the ...
Multiple controllers with AngularJS in single page app
...-div "ng-app" tags) if only your first controller works. (I remember this from my Angular newbie days.)
– ftexperts
Oct 28 '14 at 4:11
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