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How do I check that a number is float or integer?
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Creating an R dataframe row-by-row
...code in R.
If you can, allocate your entire data.frame up front:
N <- 1e4 # total number of rows to preallocate--possibly an overestimate
DF <- data.frame(num=rep(NA, N), txt=rep("", N), # as many cols as you need
stringsAsFactors=FALSE) # you don't know levels y...
How to comment out a block of Python code in Vim
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13 Answers
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It is more efficient to use if-return-return or if-else-return?
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201
Since the return statement terminates the execution of the current function, the two forms are e...
How to get the nth occurrence in a string?
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11 Answers
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Guards vs. if-then-else vs. cases in Haskell
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From a technical standpoint, all three versions are equivalent.
That being said, my rule of t...
How to escape braces (curly brackets) in a format string in .NET
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How to tell which commit a tag points to in Git?
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19 Answers
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SortedList, SortedDictionary and Dictionary
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102
When iterating over the elements in either of the two, the elements will be sorted. Not so wi...
Batch file to delete files older than N days
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1085
Enjoy:
forfiles -p "C:\what\ever" -s -m *.* -d <number of days> -c "cmd /c del @path"
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