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Creating an abstract class in Objective-C
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edited Sep 11 '11 at 17:43
mblackwell8
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How to sort a file, based on its numerical values for a field?
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Andrew WhiteAndrew White
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Find indices of elements equal to zero in a NumPy array
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numpy.where() is my favorite.
>>> x = numpy.array([1,0,2,0,3,0,4,5,6,7,8])
>>> numpy.where(x == 0)[0]
array([1, 3, 5])
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What's the point of const pointers?
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edited Feb 27 '14 at 10:24
answered Oct 10 '11 at 15:56
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How to check whether a file is empty or not?
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edited Dec 7 '14 at 21:22
Achal Dave
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Relative frequencies / proportions with dplyr
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mutate(freq = n / sum(n))
# am gear n freq
# 1 0 3 15 0.7894737
# 2 0 4 4 0.2105263
# 3 1 4 8 0.6153846
# 4 1 5 5 0.3846154
From the dplyr vignette:
When you group by multiple variables, each summary peels off one level of the grouping. That makes it easy to prog...
Python “SyntaxError: Non-ASCII character '\xe2' in file”
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147
You've got a stray byte floating around. You can find it by running
with open("x.py") as fp:
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How to implement common bash idioms in Python? [closed]
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144
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Any shell has several sets of features.
The Essential Linux/Unix commands. ...
What are the differences between type() and isinstance()?
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All Workers Are Essential
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answered Oct 11 '09 at 4:31
Alex MartelliA...
Try-catch speeding up my code?
... Lightness Races in Orbit
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answered Jan 20 '12 at 20:14
Eric LippertEric Lippert
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