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Pass a data.frame column name to a function
...ou can just use the column name directly:
df <- data.frame(A=1:10, B=2:11, C=3:12)
fun1 <- function(x, column){
max(x[,column])
}
fun1(df, "B")
fun1(df, c("B","A"))
There's no need to use substitute, eval, etc.
You can even pass the desired function as a parameter:
fun1 <- function(x...
ActiveRecord: size vs count
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Jo Liss
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answered May 21 '11 at 17:10
apneadivingapneadiving
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What C++ Smart Pointer Implementations are available?
...I do use it regularly although not always in the most optimized way.
C++11
std::unique_ptr - This is our friend who will be replacing std::auto_ptr it will be quite similar except with the key improvements to correct the weaknesses of std::auto_ptr like working with arrays, lvalue protection via...
What does Expression.Quote() do that Expression.Constant() can’t already do?
... Eric LippertEric Lippert
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When is the thread pool used?
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Community♦
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answered Mar 25 '14 at 19:44
JasonJason
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How are msys, msys2, and msysgit related to each other?
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edited Nov 29 '19 at 21:11
Peter Mortensen
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Use find command but exclude files in two directories
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sampson-chensampson-chen
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How do I lowercase a string in Python?
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answered Jul 23 '11 at 3:09
Petar IvanovPetar Ivanov
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Differences between Java 8 Date Time API (java.time) and Joda-Time
...eno Hochschild
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13
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How to remove all line breaks from a string
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edited Sep 2 '13 at 11:55
answered May 29 '12 at 19:18
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