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Extract subset of key-value pairs from Python dictionary object?
I have a big dictionary object that has several key value pairs (about 16), but I am only interested in 3 of them. What is the best way (shortest/efficient/most elegant) to achieve that?
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Removing duplicates from a list of lists
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>>> k = [[1, 2], [4], [5, 6, 2], [1, 2], [3], [4]]
>>> import itertools
>>> k.sort()
>>> list(k for k,_ in itertools.groupby(k))
[[1, 2], [3], [4], [5, 6, 2]]
itertools often offers the fastest and mo...
Elegant way to invert a map in Scala
...ning Scala currently and needed to invert a Map to do some inverted value->key lookups. I was looking for a simple way to do this, but came up with only:
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Check if at least two out of three booleans are true
An interviewer recently asked me this question: given three boolean variables, a, b, and c, return true if at least two out of the three are true.
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How to delete items from a dictionary while iterating over it?
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EDIT:
This answer will not work for Python3 and will give a RuntimeError.
RuntimeError: dictionary changed size during iteration.
This happens because mydict.keys() returns an iterator not a list.
As pointed out in comments simply convert mydict.key...
Throwing cats out of windows
...eral case of n floors and m cats.
The main formula, a[n][m] = min(max(a[k - 1][m - 1], a[n - k][m]) + 1) : for each k in 1..n, should be self-explanatory:
If first cat is thrown from k-th floor and dies, we now have k - 1 floors to check (all below k) and m - 1 cats (a[k - 1][m - 1]).
If cat ...
Is it possible to specify your own distance function using scikit-learn K-Means Clustering?
Is it possible to specify your own distance function using scikit-learn K-Means Clustering?
8 Answers
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Finding three elements in an array whose sum is closest to a given number
...e given integer S. If there exists more than one solution, any of them is ok.
15 Answers
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Select N random elements from a List in C#
I need a quick algorithm to select 5 random elements from a generic list. For example, I'd like to get 5 random elements from a List<string> .
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Remove blank attributes from an Object in Javascript
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gontard
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answered Nov 13 '08 at 3:18
OwenOwen
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