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What does the Ellipsis object do?
While idly surfing the namespace I noticed an odd looking object called Ellipsis , it does not seem to be or do anything special, but it's a globally available builtin.
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“is” operator behaves unexpectedly with integers
...3):
The current implementation keeps an
array of integer objects for all
integers between -5 and 256, when you
create an int in that range you
actually just get back a reference to
the existing object. So it should be
possible to change the value of 1. I
suspect the behaviour of Py...
Get value from SimpleXMLElement Object
... i can't believe this is so complicated. why would they make a class called "getName" but not "getValue"? why would they print empty string if you printed it instead of converted it manually to (string). WHY??
– user151496
Oct 17 '16 at 12:31
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Is there a way to detach matplotlib plots so that the computation can continue?
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Use matplotlib's calls that won't block:
Using draw():
from matplotlib.pyplot import plot, draw, show
plot([1,2,3])
draw()
print('continue computation')
# at the end call show to ensure window won't close.
show()
Using interactive mode:
from...
How to print to stderr in Python?
...to make your code Python3-ready. I guess this could be why many people actually like it!
– MarcH
Nov 18 '14 at 19:00
18
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Extracting text OpenCV
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For some cards the bounding box does not enclose all of the text, such as half a letter getting cut off. Such as this card: i.imgur.com/tX3XrwH.jpg How can I extend every bounding bounding boxes height and width by n? Thanks for the solution it works great!
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Manually raising (throwing) an exception in Python
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How do I manually throw/raise an exception in Python?
Use the most specific Exception constructor that semantically fits your issue.
Be specific in your message, e.g.:
raise ValueError('A very specific bad thing happened.')
Don't ...
PHP Redirect with POST data
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Generate a form on Page B with all the required data and action set to Page C and submit it with JavaScript on page load. Your data will be sent to Page C without much hassle to the user.
This is the only way to do it. A redirect is a 303 HTTP header tha...
Is using a lot of static methods a bad thing?
I tend to declare as static all the methods in a class when that class doesn't require to keep track of internal states. For example, if I need to transform A into B and don't rely on some internal state C that may vary, I create a static transform. If there is an internal state C that I want to be ...
Is there an IDictionary implementation that, on missing key, returns the default value instead of th
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Indeed, that won't be efficient at all.
You could always write an extension method:
public static TValue GetValueOrDefault<TKey,TValue>
(this IDictionary<TKey, TValue> dictionary, TKey key)
{
TValue ret;
// Ignore return value
dic...