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Convert Pandas column containing NaNs to dtype `int`

... In v0.24, you can now do df = df.astype(pd.Int32Dtype()) (to convert the entire dataFrame, or) df['col'] = df['col'].astype(pd.Int32Dtype()). Other accepted nullable integer types are pd.Int16Dtype and pd.Int64Dtype. Pick your poison. ...
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Case-insensitive search in Rails model

...ot's comment does not apply to strings from user input. "#$$" is a little-known shortcut for escaping global variables with Ruby string interpolation. It's equivalent to "#{$$}". But string interpolation doesn't happen to user-input strings. Try these in Irb to see the difference: "$##" and '$##'. T...
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JUnit: how to avoid “no runnable methods” in test utils classes

... That kind of irritated me. So I made BaseTixContainerTest abstract, and now JUnit truly ignores it. Tests run: 3, Failures: 0, Errors: 0, Skipped: 0 share | improve this answer | ...
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pandas GroupBy columns with NaN (missing) values

... from pandas 1.1 you have better control over this behavior, NA values are now allowed in the grouper using dropna=False share | improve this answer | follow |...
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Function overloading by return type?

...nt join " ", localtime(); # printed "58 11 2 14 0 109 3 13 0" for me right now print scalar localtime(); # printed "Wed Jan 14 02:12:44 2009" for me right now. Every operator in Perl does something in scalar context and something in list context, and they may be different, as illustrated. (This i...
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git working on two branches simultaneously

... This should be the new accepted answer, since 2.5.X is now the recommended version, even for windows i.imgur.com/oQvUhVl.png git-scm.com/download/win – RAnders00 Sep 4 '15 at 18:56 ...
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Upgrading PHP in XAMPP for Windows?

I would like to know how you upgrade PHP in Xampp for Windows? I tried to download the latest PHP version from the main PHP site but when I check (phpinfo) I still get that the previous version is still in use. ...
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How do I create a self-signed certificate for code signing on Windows?

...ndows Server 2012, Windows Server 2012 R2, or Windows 8.1 then MakeCert is now deprecated, and Microsoft recommends using the PowerShell Cmdlet New-SelfSignedCertificate. If you're using an older version such as Windows 7, you'll need to stick with MakeCert or another solution. Some people suggest ...
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What does the ^ operator do in Java?

...Integer.parseInt as a programming exercise (^ denotes exponentiation from now on). The OP's intention was to compute 8*10^6 + 6*10^5 + 7*10^4 + 5*10^3 + 3*10^2 + 0*10^1 + 9*10^0 = 8675309; the next part of this answer addresses that exponentiation is not necessary for this task. Horner's scheme ...
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Forward declaring an enum in C++

... The reason the enum can't be forward declared is that without knowing the values, the compiler can't know the storage required for the enum variable. C++ Compiler's are allowed to specify the actual storage space based on the size necessary to contain all the values specified. If all t...