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multiprocessing.Pool: When to use apply, apply_async or map?
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Back in the old days of Python, to call a function with arbitrary arguments, you would use apply:
apply(f,args,kwargs)
apply still exists in Python2.7 though not in Python3, and is generally not used anymore. Nowadays,
f(*args,**kwargs)
is pr...
ValueError: numpy.dtype has the wrong size, try recompiling
I just installed pandas and statsmodels package on my python 2.7
When I tried "import pandas as pd", this error message comes out.
Can anyone help? Thanks!!!
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Printing Lists as Tabular Data
I am quite new to Python and I am now struggling with formatting my data nicely for printed output.
13 Answers
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Why does python use 'else' after for and while loops?
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It's a strange construct even to seasoned Python coders. When used in conjunction with for-loops it basically means "find some item in the iterable, else if none was found do ...". As in:
found_obj = None
for obj in objects:
if obj.key == search_key:
fou...
When is “i += x” different from “i = i + x” in Python?
...lace_concat, and those C API functions have stricter requirements than the Python dunder methods, and… But I don't think that's relevant to the answer. The main distinction is that += tries to do an in-place add before falling back to acting like +, which I think you've already explained.
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Remove scroll bar track from ScrollView in Android
...ally) scrollable. So I've wrapped the WebView in a ScrollView in my layout XML, but no matter what I do I can't seem to be able to remove the scroll bar track from the right side of the scroll view. Even worse, I can't seem to be able to change the background colour of the scroll bar track.
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Python unittest - opposite of assertRaises?
...code you would raise a KeyError, that would be an error, not a failure. In python - differently than some other languages - Exceptions are routinely used for control flow, this is why we have the except <ExceptionName> syntax indeed. To that regard, user9876's solution is simply wrong.
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What is the purpose of the word 'self'?
What is the purpose of the self word in Python? I understand it refers to the specific object created from that class, but I can't see why it explicitly needs to be added to every function as a parameter. To illustrate, in Ruby I can do this:
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Solving “Who owns the Zebra” programmatically?
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Here's a solution in Python based on constraint-programming:
from constraint import AllDifferentConstraint, InSetConstraint, Problem
# variables
colors = "blue red green white yellow".split()
nationalities = "Norwegian German Dane Swed...
Split string using a newline delimiter with Python
...w.com%2fquestions%2f22042948%2fsplit-string-using-a-newline-delimiter-with-python%23new-answer', 'question_page');
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