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What is the difference between NaN and None?

...= pd.Series([1, None], dtype=object) s_good = pd.Series([1, np.nan]) In [13]: s_bad.dtype Out[13]: dtype('O') In [14]: s_good.dtype Out[14]: dtype('float64') Jeff comments (below) on this: np.nan allows for vectorized operations; its a float value, while None, by definition, forces object ty...
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Python regex find all overlapping matches?

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How to map with index in Ruby?

... answered Jan 15 '11 at 1:37 sepp2ksepp2k 331k4747 gold badges635635 silver badges652652 bronze badges ...
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How do I detach objects in Entity Framework Code First?

... saluce 11.4k33 gold badges4444 silver badges6363 bronze badges answered Apr 8 '11 at 20:00 Ladislav MrnkaLadislav...
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finding the type of an element using jQuery

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How can I open Windows Explorer to a certain directory from within a WPF app?

... 314 Why not Process.Start(@"c:\test");? ...
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Cannot serve WCF services in IIS on Windows 8

... Callum Watkins 2,22222 gold badges2323 silver badges4040 bronze badges answered Jul 12 '12 at 20:35 faesterfaester ...
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Use rvmrc or ruby-version file to set a project gemset with RVM?

... 372 If your .rvmrc file contains custom shell code, continue using .rvmrc as it allows you to incl...
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Why should I prefer single 'await Task.WhenAll' over multiple awaits?

...| edited Jun 25 '19 at 16:31 answered Aug 19 '13 at 10:02 u...
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Dynamically creating keys in a JavaScript associative array

... | edited Aug 3 '12 at 1:40 bkaid 48.4k2020 gold badges107107 silver badges126126 bronze badges ...