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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...
Create an index on a huge MySQL production table without table locking
... 0m0.009s
8 real 0m0.009s
9 real 0m0.009s
10 real 0m0.009s
11 real 0m0.009s
Vs read operations which don't block (swap the line comment in the script):
1 real 0m0.010s
2 real 0m0.009s
3 real 0m0.009s
4 real 0m0.010s
5 real 0m0.009s
Index Update - START...
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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Android Game Keeps Getting Hacked [closed]
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11 Answers
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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...
Use find command but exclude files in two directories
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sampson-chensampson-chen
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How can I color Python logging output?
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xoloxxolox
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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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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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