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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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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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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...
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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...
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Understanding events and event handlers in C#

... understand the purpose of events, especially within the context of creating user interfaces. I think this is the prototype for creating an event: ...
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How to get the first non-null value in Java?

...at is, is there any way to return the first non-null value of several variables? 12 Answers ...
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CSS '>' selector; what is it? [duplicate]

I've seen the "greater than" ( > ) used in CSS code a few times, but I can't work out what it does. What does it do? 7 A...
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How to iterate through two lists in parallel?

I have two iterables in Python, and I want to go over them in pairs: 8 Answers 8 ...
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Javascript array search and remove string?

...pdating this thread with a more recent 1-line solution: let arr = ['A', 'B', 'C']; arr = arr.filter(e => e !== 'B'); // will return ['A', 'C'] The idea is basically to filter the array by selecting all elements different to the element you want to remove. Note: will remove all occurrences. ...
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Why Would I Ever Need to Use C# Nested Classes [duplicate]

I'm trying to understand about nested classes in C#. I understand that a nested class is a class that is defined within another class, what I don't get is why I would ever need to do this. ...