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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...
Guards vs. if-then-else vs. cases in Haskell
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122
From a technical standpoint, all three versions are equivalent.
That being said, my rule of t...
SVN undo delete before commit
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svn revert deletedDirectory
Here's the documentation for the svn revert command.
EDIT
If dele...
Can I query MongoDB ObjectId by date?
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Linux command (like cat) to read a specified quantity of characters
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194
head works too:
head -c 100 file # returns the first 100 bytes in the file
..will extract ...
How do I check that a number is float or integer?
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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...
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...
How to comment out a block of Python code in Vim
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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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