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dplyr summarise: Equivalent of “.drop=FALSE” to keep groups with zero length in output
...g summarise with plyr 's ddply function, empty categories are dropped by default. You can change this behavior by adding .drop = FALSE . However, this doesn't work when using summarise with dplyr . Is there another way to keep empty categories in the result?
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How to modify list entries during for loop?
...rings, and I want to strip the strings themselves. Does replacement of mutable values count as modification?
9 Answers
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Pandas groupby: How to get a union of strings
... df = read_csv(StringIO(data),sep='\s+')
In [5]: df
Out[5]:
A B C
0 1 0.749065 This
1 2 0.301084 is
2 3 0.463468 a
3 4 0.643961 random
4 1 0.866521 string
5 2 0.120737 !
In [6]: df.dtypes
Out[6]:
A int64
B float64
C object
dtype: obj...
Error in finding last used cell in Excel with VBA
...the last row. This will also cover the best practices to follow when finding the last row. And hence I will keep on updating it whenever I come across a new scenario/information.
Unreliable ways of finding the last row
Some of the most common ways of finding last row which are highly unreliable ...
Easy way to concatenate two byte arrays
What is the easy way to concatenate two byte arrays?
12 Answers
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What's the difference between array_merge and array + array?
A fairly simple question. What's the difference between:
9 Answers
9
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Relationship between SciPy and NumPy
SciPy appears to provide most (but not all [1]) of NumPy's functions in its own namespace. In other words, if there's a function named numpy.foo , there's almost certainly a scipy.foo . Most of the time, the two appear to be exactly the same, oftentimes even pointing to the same function object.
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Combine the first two commits of a Git repository?
Suppose you have a history containing the three commits A, B and C :
8 Answers
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LINQ Aggregate algorithm explained
This might sound lame, but I have not been able to find a really good explanation of Aggregate .
12 Answers
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Many-to-many relationship with the same model in rails?
...itional information with the association? (Additional fields in the join table.)
Do the associations need to be implicitly bi-directional?
(If post A is connected to post B, then post B is also connected to post A.)
That leaves four different possibilities. I'll walk over these below.
For referen...