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Pass a data.frame column name to a function
I'm trying to write a function to accept a data.frame ( x ) and a column from it. The function performs some calculations on x and later returns another data.frame. I'm stuck on the best-practices method to pass the column name to the function.
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How to avoid type safety warnings with Hibernate HQL results?
For example I have such query:
15 Answers
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How to change language settings in R
My error messages are displayed in French. How can I change my system language setting so the error messages will be displayed in English?
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Sublime Text 2: Trim trailing white space on demand
I know that Sublime Text 2 can delete the trailing white space on files upon saving.
5 Answers
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What is the difference between URI, URL and URN? [duplicate]
What's the difference between an URI, URL and URN? I have read a lot of sites (even Wikipedia) but I don't understand it.
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How to make child process die after parent exits?
Suppose I have a process which spawns exactly one child process. Now when the parent process exits for whatever reason (normally or abnormally, by kill, ^C, assert failure or anything else) I want the child process to die. How to do that correctly?
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How to save a data.frame in R?
I made a data.frame in R that is not very big, but it takes quite some time to build. I would to save it as a file, which I can than again open in R?
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Best way to create enum of strings?
What is the best way to have a enum type represent a set of strings?
8 Answers
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Nullable Foreign Key bad practice?
Let's say you have a table Orders with a foreign key to a Customer Id. Now, suppose you want to add an Order without a Customer Id, (whether that should be possible is another question) you would have to make the foreign key NULL... Is that bad practice or would you rather work with a link table bet...
Is it possible to reference one CSS rule within another?
For example if I have the following HTML:
7 Answers
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