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What are “connecting characters” in Java identifiers?
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I'm not sure that actually fully answers the (implied) question of which characters may start a Java identifier. Following links we end up at Character.isJavaIdentifierStart() which states A character may start a Java identifier if and only if one...
Psql list all tables
... CASE c.relkind WHEN 'r' THEN 'table' WHEN 'v' THEN 'view' WHEN 'i' THEN 'index' WHEN 'S' THEN 'sequence' WHEN 's' THEN 'special' WHEN 'f' THEN 'foreign table' END as "Type",
pg_catalog.pg_get_userbyid(c.relowner) as "Owner"
FROM pg_catalog.pg_class c
LEFT JOIN pg_catalog.pg_namespace n ON n...
M_PI works with math.h but not with cmath in Visual Studio
...) and suddenly it compile perfectly.
Try moving it higher up the page. Totally unsure as to why this would cause issues though.
Edit: Figured it out. The #include <math.h> occurs within cmath's header guards. This means that something higher up the list of #includes is including cmath with...
How to create a custom string representation for a class object?
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@RobertSiemer Why? While his answer is not specifically targeting the OP's question, it's still helpful. It helped me. And at a glance, I don't see any question asking for instance implementation. So probably people land on this page first.
– akinuri
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How do I diff the same file between two different commits on the same branch?
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The .. isn't really necessary, though it'll work with it (except in fairly old versions, maybe). You can also use git log or gitk to find SHA1s to use, should the two commits be very far apart. gitk also has a "diff selected -> this" and...
Super-simple example of C# observer/observable with delegates
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The observer pattern is usually implemented with events.
Here's an example:
using System;
class Observable
{
public event EventHandler SomethingHappened;
public void DoSomething() =>
SomethingHappened?.Invoke(this, EventArgs.Empt...
Best documentation for Boost:asio?
...io can be found in a (free) boost book at http://en.highscore.de/cpp/boost/index.html. The chapter on asio provides a general overview and then goes as far as how to develop your own custom asio extensions. Really fantastic effort by Boris Schäling!
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bash: mkvirtualenv: command not found
...ckages written in Python. Many packages can be found in the Python Package Index (PyPI).
sudo apt-get install python-pip
Install Virtual Environment. Used to create virtual environment, to install packages and dependencies of multiple projects isolated from each other.
sudo pip install virtualenv
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How can I quantify difference between two images?
...s on the first image to edges on the second.
Is there noise in the image?
All sensors pollute the image with some amount of noise. Low-cost sensors have more noise. You may wish to apply some noise reduction before you compare images. Blur is the most simple (but not the best) approach here.
What k...
Convert nested Python dict to object?
...; s.a
1
>>> s.b
{'c': 2}
>>> s.c
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
AttributeError: 'MyStruct' object has no attribute 'c'
>>> s.d
['hi']
The alternative (original answer contents) is:
class Struct:
def __init__(self...