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python: How do I know what type of exception occurred?
I have a function called by the main program:
15 Answers
15
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Absolute vs relative URLs
...ed Jan 5 '10 at 9:33
Daniel VassalloDaniel Vassallo
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How to list all functions in a Python module?
I have a python module installed on my system and I'd like to be able to see what functions/classes/methods are available in it.
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A simple explanation of Naive Bayes Classification
... & part two being the confusion surrounding Training set.
In general all of Machine Learning Algorithms need to be trained for supervised learning tasks like classification, prediction etc. or for unsupervised learning tasks like clustering.
During the training step, the algorithms are taught...
Get exception description and stack trace which caused an exception, all as a string
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See the traceback module, specifically the format_exc() function. Here.
import traceback
try:
raise ValueError
except ValueError:
tb = traceback.format_exc()
else:
tb = "No error"
finally:
print tb
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How to select a single field for all documents in a MongoDB collection?
... include several fields. In the following operation, find() method returns all documents that match the query. In the result set, only the item and qty fields and, by default, the _id field return in the matching documents.
db.inventory.find( { type: 'food' }, { item: 1, qty: 1 } )
In this example ...
Should I use a class or dictionary?
...ould your __init__ code go?
Classes are for bundling related data (and usually code).
Dictionaries are for storing key-value relationships, where usually the keys are all of the same type, and all the values are also of one type. Occasionally they can be useful for bundling data when the key/attri...
What are some (concrete) use-cases for metaclasses?
...a couple functions I found that I was able to increment the figure count, call draw manually, etc, but I needed to do these before and after every plotting call. So to create both an interactive plotting wrapper and an offscreen plotting wrapper, I found it was more efficient to do this via metacla...
Check if $_POST exists
...sts and if it does, print it inside another string, if not, don't print at all.
14 Answers
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Understanding the difference between __getattr__ and __getattribute__
...oesn't explicitly manage and do that via __getattr__ method.
Python will call this method whenever you request an attribute that hasn't already been defined, so you can define what to do with it.
A classic use case:
class A(dict):
def __getattr__(self, name):
return self[name]
a = A()...