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Mean per group in a data.frame [duplicate]
I have a data.frame and I need to calculate the mean per group (i.e. per Month , below).
8 Answers
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How to swap the buffers in 2 windows emacs
I am using emacs I find that sometimes I have 2 files separated into 2 windows.
8 Answers
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Can't compare naive and aware datetime.now()
I am trying to compare the current date and time with dates and times specified in models using comparison operators:
7 Ans...
What does “|=” mean? (pipe equal operator)
I tried searching using Google Search and Stack Overflow, but it didn't show up any results. I have seen this in opensource library code:
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How to get a subset of a javascript object's properties
Say I have an object:
25 Answers
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What does the ??!??! operator do in C?
I saw a line of C that looked like this:
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How to verify if a file exists in a batch file?
I have to create a .BAT file that does this:
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convert a JavaScript string variable to decimal/money
How can we convert a JavaScript string variable to decimal?
7 Answers
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How to create GUID / UUID?
I'm trying to create globally-unique identifiers in JavaScript. I'm not sure what routines are available on all browsers, how "random" and seeded the built-in random number generator is, etc.
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Take a char input from the Scanner
I am trying to find a way to take a char input from the keyboard.
22 Answers
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