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Easy way to concatenate two byte arrays
What is the easy way to concatenate two byte arrays?
12 Answers
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C++ equivalent of java's instanceof
...>doSomething();
}
This requires your compiler to have rtti support enabled.
EDIT:
I've had some good comments on this answer!
Every time you need to use a dynamic_cast (or instanceof) you'd better ask yourself whether it's a necessary thing. It's generally a sign of poor design.
Typical wor...
What's the difference between array_merge and array + array?
A fairly simple question. What's the difference between:
9 Answers
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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 :
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8
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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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Why do I need 'b' to encode a string with Base64?
Following this python example , I encode a string as Base64 with:
5 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...
Convert columns to string in Pandas
... your keys to strings):
In [11]: df = pd.DataFrame([['A', 2], ['A', 4], ['B', 6]])
In [12]: df.to_json()
Out[12]: '{"0":{"0":"A","1":"A","2":"B"},"1":{"0":2,"1":4,"2":6}}'
In [13]: df[0].to_json()
Out[13]: '{"0":"A","1":"A","2":"B"}'
Note: you can pass in a buffer/file to save this to, along wi...
Apply multiple functions to multiple groupby columns
The docs show how to apply multiple functions on a groupby object at a time using a dict with the output column names as the keys:
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