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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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How do I check in JavaScript if a value exists at a certain array index?
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Conceptually, arrays in JavaScript contain array.length elements, starting with array[0] up until array[array.length - 1]. An array element with index i is defined to be part of the array if i is between 0 and array.length - 1 inclu...
Capture characters from standard input without waiting for enter to be pressed
...oo much on the terminal used that may be connected with stdin (they are usually line buffered). You can, however use a library for that:
conio available with Windows compilers. Use the _getch() function to give you a character without waiting for the Enter key. I'm not a frequent Windows developer...
Number of processors/cores in command line
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Make sure to nproc --all for all installed Processing Units. Without --all, nproc only shows Processing Units available to the current process. Read the man page for more details. MMV.
– JamesThomasMoon1979
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Implementing slicing in __getitem__
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The __getitem__() method will receive a slice object when the object is sliced. Simply look at the start, stop, and step members of the slice object in order to get the components for the slice.
>>> class C(object):
......
Tools to selectively Copy HTML+CSS+JS From A Specific Element of DOM [closed]
Like most web developers, I occasionally like to look at the source of websites to see how their markup is built. Tools like Firebug and Chrome Developer Tools make it easy to inspect the code, but if I want to copy a specific section and play around with it locally, it would be a pain to copy all t...
How to run a PowerShell script from a batch file
... would have otherwise. In a way it's merely a convenience to avoid accidentally running things you may not want to run. Similar to having to prefix commands in the current directory with ./ and having an executable flag on Unix.
– Joey
Nov 6 '16 at 14:26
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Delete a key from a MongoDB document using Mongoose
...de-mongodb-native driver. Each model has a collection object that contains all the methods that node-mongodb-native offers. So you can do the action in question by this:
User.collection.update({_id: user._id}, {$unset: {field: 1 }});
Since version 2.0 you can do:
User.update({_id: user._id}, {$u...
Cooler ASCII Spinners? [closed]
... even in random order http://www.fileformat.info/info/unicode/block/braille_patterns/images.htm
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How do I update/upsert a document in Mongoose?
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Mongoose now supports this natively with findOneAndUpdate (calls MongoDB findAndModify).
The upsert = true option creates the object if it doesn't exist. defaults to false.
var query = {'username': req.user.username};
req.newData.username = req.user.username;
MyModel.findOneAndUpd...