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How to make a great R reproducible example

When discussing performance with colleagues, teaching, sending a bug report or searching for guidance on mailing lists and here on Stack Overflow, a reproducible example is often asked and always helpful. ...
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Declare a constant array

I have tried: 4 Answers 4 ...
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What is the fastest way to get the value of π?

I'm looking for the fastest way to obtain the value of π, as a personal challenge. More specifically, I'm using ways that don't involve using #define constants like M_PI , or hard-coding the number in. ...
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Does MySQL ignore null values on unique constraints?

I have an email column that I want to be unique. But I also want it to accept null values. Can my database have 2 null emails that way? ...
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difference between each.with_index and each_with_index in Ruby?

I'm really confused about the difference between each.with_index and each_with_index . They have different types but seem to be identical in practice. ...
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How to remove jar file from local maven repository which was added with install:install-file?

I use above command to install local jar into maven local repo. Now I have got the dependency from maven repo. I want to remove this from local repo. How to clean it ? ...
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error upon assigning Layout: BoxLayout can't be shared

I have this Java JFrame class, in which I want to use a boxlayout, but I get an error saying java.awt.AWTError: BoxLayout can't be shared . I've seen others with this problem, but they solved it by creating the boxlayout on the contentpane, but that is what I'm doing here. Here's my code: ...
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instantiate a class from a variable in PHP?

I know this question sounds rather vague so I will make it more clear with an example: 5 Answers ...
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Where are environment variables stored in registry?

I need to access an environment variable remotely. To do this I think the best way is to read it from registry. 4 Answers...
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AngularJS ng-click stopPropagation

I have a click Event on a table row and in this row there is also a delete Button with a click Event. When i click the delete button the click Event on the row is also fired. ...