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How to create NS_OPTIONS-style bitmask enumerations in Swift?
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Reverse a string in Python
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How about:
>>> 'hello world'[::-1]
'dlrow olleh'
This is extended slice syntax. It works by doing [begin:end:step] - by leaving begin and end off and specifying a step of -1, it reverses a string.
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Can hash tables really be O(1)?
It seems to be common knowledge that hash tables can achieve O(1), but that has never made sense to me. Can someone please explain it? Here are two situations that come to mind:
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'Must Override a Superclass Method' Errors after importing a project into Eclipse
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In a javascript array, how do I get the last 5 elements, excluding the first element?
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You can call:
arr.slice(Math.max(arr.length - 5, 1))
If you don't want to exclude the first element, use
arr.slice(Math.max(arr.length - 5, 0))
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Replacement for “rename” in dplyr
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148
dplyr version 0.3 added a new rename() function that works just like plyr::rename().
df <-...
Changing the “tick frequency” on x or y axis in matplotlib?
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How to extract the decision rules from scikit-learn decision-tree?
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