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How does one reorder columns in a data frame?
... has four columns like so df[,c(1,2,3,4)].
Note the first comma means keep all the rows, and the 1,2,3,4 refers to the columns.
To change the order as in the above question do df2[,c(1,3,2,4)]
If you want to output this file as a csv, do write.csv(df2, file="somedf.csv")
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“405 method not allowed” in IIS7.5 for “PUT” method
...eb-api/overview/testing-and-debugging/…
– Tod Birdsall
Mar 17 '15 at 14:28
Great, you saved me hours of painful debu...
Why does flowing off the end of a non-void function without returning a value not produce a compiler
...C++ 6.6.3/2 is not the same in C.
gcc will give you a warning if you call it with -Wreturn-type option.
-Wreturn-type Warn whenever a function is defined with a return-type that
defaults to int. Also warn about any
return statement with no return-value
in a function whose return-type ...
Create web service proxy in Visual Studio from a WSDL file
... URL property you can set on the fly, and a bunch of methods that you can call. It'll also generate classes for all/any complex objects passed across the service interface.
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Why are arrays of references illegal?
...question about standard I can cite the C++ Standard §8.3.2/4:
There shall be no references to references, no arrays of references, and no pointers to references.
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Difference between SurfaceView and View?
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Views are all drawn on the same GUI thread which is also used for all user interaction.
So if you need to update GUI rapidly or if the rendering takes too much time and affects user experience then use SurfaceView.
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How to initialize all members of an array to the same value in Swift?
I have a large array in Swift. I want to initialize all members to the same value (i.e. it could be zero or some other value). What would be the best approach?
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Codesign error: Provisioning profile cannot be found after deleting expired profile
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Sometimes your xcode project file gets messed up, especially if you have an old project and first created it with an older version of xcode/iphone sdk. What you need to do is open up the project file in a text editor, search for the 'long string' from your error and manually eras...
Regex to validate date format dd/mm/yyyy
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Edit February 14th 2019: I've removed a comma that was in the regex which allowed dates like 29-0,-11
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What is a postback?
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When does it happen?
A postback originates from the client browser. Usually one of the controls on the page will be manipulated by the user (a button clicked or dropdown changed, etc), and this control will initiate a postback. The state of this control, plus all other controls on the page,(know...