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Two way/reverse map [duplicate]
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>>> del d['foo']
>>> d['bar']
Traceback (most recent call last):
File "<stdin>", line 7, in <module>
KeyError: 'bar'
I'm sure I didn't cover all the cases, but that should get you started.
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“ImportError: No module named” when trying to run Python script
...the notebook to operate from in your ipython_notebook_config.py file (typically using the c.NotebookManager.notebook_dir setting).
The solution is to provide the python interpreter with the path-to-your-module. The simplest solution is to append that path to your sys.path list. In your notebook, fi...
How to process SIGTERM signal gracefully?
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@Mausy5043 Python allows you to not have parenthesis for defining classes. Although it's perfectly fine for python 3.x, but for python 2.x, best practice is to use "class XYZ(object):". Reason being: docs.python.org/2/reference/datamodel.html#...
Is it possible to create static classes in PHP (like in C#)?
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You can have static classes in PHP but they don't call the constructor automatically (if you try and call self::__construct() you'll get an error).
Therefore you'd have to create an initialize() function and call it in each method:
<?php
class Hello
{
private static...
How do I get the path to the current script with Node.js?
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So basically you can do this:
fs.readFile(path.resolve(__dirname, 'settings.json'), 'UTF-8', callback);
Use resolve() instead of concatenating with '/' or '\' else you will run into cross-platform issues.
Note: __dirname is the l...
res.sendFile absolute path
...pond with index.html on every request, because I'm using a star * to catch all files that weren't found in your static (public) directory; which is the most common use case for web-apps. Change to / to return the index only in the root path.
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What does __FILE__ mean in Ruby?
I see this all the time in Ruby:
4 Answers
4
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What is the 'new' keyword in JavaScript?
...n's external, accessible, prototype object (every function object automatically has a prototype property).
It makes the this variable point to the newly created object.
It executes the constructor function, using the newly created object whenever this is mentioned.
It returns the newly created objec...
multiprocessing.Pool: When to use apply, apply_async or map?
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Back in the old days of Python, to call a function with arbitrary arguments, you would use apply:
apply(f,args,kwargs)
apply still exists in Python2.7 though not in Python3, and is generally not used anymore. Nowadays,
f(*args,**kwargs)
is preferred. The...
Example for boost shared_mutex (multiple reads/one write)?
I have a multithreaded app that has to read some data often, and occasionally that data is updated. Right now a mutex keeps access to that data safe, but it's expensive because I would like multiple threads to be able to read simultaneously, and only lock them out when an update is needed (the updat...