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flodel has asked 47 questions and find answers to 436 problems.

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flodel questions

conditional inclusion of arguments in a function call
automatically detect date columns when reading a file into a data.frame
why does `x[0]` return a zero-length vector?
Why does `a ^ b` return a numeric when both `a` and `b` are integers?
preserve old (pre 3.1.0) type.convert behavior
setting environment variables programmatically
`as.na` function
Why are some of the logical operators so slow?
"replace" function examples
data.table "key indices" or "group counter"

flodel answers

LD_LIBRARY_PATH precendence and trouble with compiling
Counting the number of non-zero's in data frame or matrix
Greedy optimization in R
How to combine a data frame and a vector
Calculating a non-overlapping moving average
Faster modulo or equality checking in R (or good ways to vectorize)
Sum in a Cross Table
Return list containing indices of each element in a vector
R:intersection of matrices
Given a matrix, x, set all elements below the main diagonal to 0