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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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Advantage of creating a generic repository vs. specific repository for each object?
... are any major advantages to creating a generic IRepository interface that all repositories implement, vs. each Repository having its own unique interface and set of methods.
...
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...
bash: pip: command not found
I downloaded pip and ran python setup.py install and everything worked just fine. The very next step in the tutorial is to run pip install <lib you want> but before it even tries to find anything online I get an error "bash: pip: command not found".
...
Optimistic vs. Pessimistic locking
...revert all current pending changes which might involve both table rows and index records.
For this reason, pessimistic locking might be ore suitable when conflicts happen frequently, as it reduces the chance of rolling back transactions.
...
How to check if running in Cygwin, Mac or Linux?
...
Usually, uname with its various options will tell you what environment you're running in:
pax> uname -a
CYGWIN_NT-5.1 IBM-L3F3936 1.5.25(0.156/4/2) 2008-06-12 19:34 i686 Cygwin
pax> uname -s
CYGWIN_NT-5.1
And, accordin...
MongoDB drop every database
..."dropping db " + db.getName() );
db.dropDatabase();
}
save it to dropall.js and then execute:
mongo dropall.js
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Create a custom event in Java
...else in the package
interface ThrowListener {
public void Catch();
}
/*_____________________________________________________________*/class Thrower {
//list of catchers & corresponding function to add/remove them in the list
List<ThrowListener> listeners = new ArrayList<ThrowLis...
mingw-w64 threads: posix vs win32
I'm installing mingw-w64 on Windows and there are two options: win32 threads and posix threads. I know what is the difference between win32 threads and pthreads but I don't understand what is the difference between these two options. I doubt that if I will choose posix threads it will prevent me fro...
Why is “import *” bad?
...ed (readability).
Because you can't use cool tools like pyflakes to statically detect errors in your code.
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