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“Inner exception” (with traceback) in Python?
My background is in C# and I've just recently started programming in Python. When an exception is thrown I typically want to wrap it in another exception that adds more information, while still showing the full stack trace. It's quite easy in C#, but how do I do it in Python?
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python: How do I know what type of exception occurred?
...ns, but no one seems to want to tell you why, which is essential to understanding when you can break the "rule". Here is an explanation. Basically, it's so that you don't hide:
the fact that an error occurred
the specifics of the error that occurred (error hiding antipattern)
So as long as you ...
TypeError: module.__init__() takes at most 2 arguments (3 given)
... screwy.
Change your import statement to:
from Object import ClassName
and your class definition to:
class Visitor(ClassName):
or
change your class definition to:
class Visitor(Object.ClassName):
etc
share
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How do I avoid capturing self in blocks when implementing an API?
I have a working app and I'm working on converting it to ARC in Xcode 4.2. One of the pre-check warnings involves capturing self strongly in a block leading to a retain cycle. I've made a simple code sample to illustrate the issue. I believe I understand what this means but I'm not sure the "corre...
What does “hashable” mean in Python?
...ue which never changes during its lifetime (it needs a __hash__() method), and can be compared to other objects (it needs an __eq__() or __cmp__() method). Hashable objects which compare equal must have the same hash value.
Hashability makes an object usable as a dictionary key and a set member...
Python multiprocessing pool.map for multiple arguments
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The answer to this is version- and situation-dependent. The most general answer for recent versions of Python (since 3.3) was first described below by J.F. Sebastian.1 It uses the Pool.starmap method, which accepts a sequence of argument tuples. It then au...
Exiting from python Command Line
To exit from Python command line, I have to type exit(). If I type exit, it says
11 Answers
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Format date and time in a Windows batch script
In a Windows (Windows XP) batch script I need to format the current date and time for later use in files names, etc.
33 An...
How to import other Python files?
...t__): Because this function is meant for use by the Python interpreter and not for general use it is better to use importlib.import_module() to programmatically import a module.
– Tadhg McDonald-Jensen
Feb 23 '16 at 15:04
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How do I plot in real-time in a while loop using matplotlib?
...ib.pyplot as plt
plt.axis([0, 10, 0, 1])
for i in range(10):
y = np.random.random()
plt.scatter(i, y)
plt.pause(0.05)
plt.show()
Note some of the changes:
Call plt.pause(0.05) to both draw the new data and it runs the GUI's event loop (allowing for mouse interaction).
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