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error: command 'gcc' failed with exit status 1 while installing eventlet
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374
Your install is failing because you don't have the python development headers installed. You can...
How do I make and use a Queue in Objective-C?
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edited Feb 1 '10 at 17:40
Quinn Taylor
43.3k1515 gold badges107107 silver badges127127 bronze badges
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What does in XML mean?
... Clonkex
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answered May 6 '10 at 20:23
Sean VieiraSean Vieira
133k2828...
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...
Explicitly calling return in a function or not
...e.
# here without calling .Primitive('return')
> (function() {10;20;30;40})()
[1] 40
# here with .Primitive('return')
> (function() {10;20;30;40;return(40)})()
[1] 40
# here return terminates flow
> (function() {10;20;return();30;40})()
NULL
> (function() {10;20;return(25);30;40})()
[1]...
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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How to sort a file, based on its numerical values for a field?
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Andrew WhiteAndrew White
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How to delete a workspace in Perforce (using p4v)?
I'm new to Perforce and have created a few workspaces as exercises for getting familiar with it. Now I would like to delete some of the workspaces. I just want to get rid of the workspaces so that they do not appear on the drop-down in the workspaces view ( do not want to do anything with actual de...
Alternatives to JavaScript
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The problem with javascript is not the language itself - it's a perfectly good prototyped and d...