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How to take the first N items from a generator or list in Python? [duplicate]
...imple syntax: array[start:stop:step]
You can omit any parameter. These are all valid: array[start:], array[:stop], array[::step]
Slicing a generator
import itertools
top5 = itertools.islice(my_list, 5) # grab the first five elements
You can't slice a generator directly in Python. itertools.i...
Drop all tables whose names begin with a certain string
How can I drop all tables whose names begin with a given string?
14 Answers
14
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Cast Int to enum in Java
... 0 or 1, i.e. a valid ordinal for that enum.
Note that in Java enums actually are classes (and enum values thus are objects) and thus you can't cast an int or even Integer to an enum.
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impr...
Vim: insert the same characters across multiple lines
...e the screen in the first line - until Esc is pressed (6.), at which point all lines will be updated.
Press Esc.
An uppercase I must be used rather than a lowercase i, because the lowercase i is interpreted as the start of a text object, which is rather useful on its own, e.g. for selecting insi...
Decorators with parameters?
...tion that will take a function and return another function. So it should really return a normal decorator. A bit confusing, right? What I mean is:
def decorator_factory(argument):
def decorator(function):
def wrapper(*args, **kwargs):
funny_stuff()
something_with...
Python Pandas: Get index of rows which column matches certain value
... frame (whose data may be gibabytes). What about dftest? Doesn't this also allocate a very large intermediate object where the returned index may be very small, or even empty. Are these magically optimized away using lazy views. If not then surely there must be an efficient way.
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Remove All Event Listeners of Specific Type
I want to remove all event listeners of a specific type that were added using addEventListener() . All the resources I'm seeing are saying you need to do this:
...
Using sections in Editor/Display templates
I want to keep all of my JavaScript code in one section; just before the closing body tag in my master layout page and just wondering the best to go about it, MVC style.
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Asserting successive calls to a mock method
Mock has a helpful assert_called_with() method . However, as far as I understand this only checks the last call to a method.
If I have code that calls the mocked method 3 times successively, each time with different parameters, how can I assert these 3 calls with their specific parameters?
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Proper use of beginBackgroundTaskWithExpirationHandler
...l need to wrap it in a background task. It's also very important that you call endBackgroundTask when you're finished - otherwise the app will be killed after its allotted time has expired.
Mine tend look something like this:
- (void) doUpdate
{
dispatch_async(dispatch_get_global_queue(DISPAT...
