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How do I delete rows in a data frame?
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The key idea is you form a set of the rows you want to remove, and keep the complement of that set.
In R, the complement of a set is given by the '-' operator.
So, assuming the data.frame is called myData:
myData[-c(2, 4, 6), ] # notice the -
Of course, don't forget to "reassign" ...
Local Storage vs Cookies
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Cookies and local storage serve different purposes. Cookies are primarily for reading server-side, local storage can only be read by the client-side. So the question is, in your app, who needs this data — the client or the server?
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How to get the nth element of a python list or a default if not available
...it: I removed the check for TypeError - probably better to let the caller handle this.
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How do you rotate a two dimensional array?
...e. Printing the matrix is the same complexitiy
– Alejandro
Aug 4 '15 at 20:34
6
For a -90 degrees...
Does the use of the “Async” suffix in a method name depend on whether the 'async' modifier is used?
... is ambiguous even from Microsoft documentation:
In Visual Studio 2012 and the .NET Framework 4.5, any method that is
attributed with the async keyword (Async in Visual Basic) is
considered an asynchronous method, and the C# and Visual Basic
compilers perform the necessary transformations ...
Rebuild or regenerate 'ic_launcher.png' from images in Android Studio
...ates a new project, that dialog lets you point
to some external .PNG file, and then when that dialog completes,
it generates 4 different pixel-sizes of images for use as
a launcher-icon.
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Git diff says subproject is dirty
I have just run a git diff, and I am getting the following output for all of my approx 10 submodules
9 Answers
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Are there good reasons not to use an ORM? [closed]
...p, I have used NHibernate for some smaller projects which I mostly coded and designed on my own. Now, before starting some bigger project, the discussion arose how to design data access and whether or not to use an ORM layer. As I am still in my apprenticeship and still consider myself a beginner ...
Why JSF calls getters multiple times
... is caused by the nature of deferred expressions #{} (note that "legacy" standard expressions ${} behave exactly the same when Facelets is used instead of JSP). The deferred expression is not immediately evaluated, but created as a ValueExpression object and the getter method behind the expression i...
Truly understanding the difference between procedural and functional
I'm really having a hard time understanding the difference between procedural and functional programming paradigms.
9 A...