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Append value to empty vector in R?
...appending for larger vectors.
set.seed(21)
values <- sample(letters, 1e4, TRUE)
vector <- character(0)
# slow
system.time( for (i in 1:length(values)) vector[i] <- values[i] )
# user system elapsed
# 0.340 0.000 0.343
vector <- character(length(values))
# fast(er)
system.time(...
Why are these constructs using pre and post-increment undefined behavior?
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14 Answers
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.toArray(new MyClass[0]) or .toArray(new MyClass[myList.size()])?
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114
Counterintuitively, the fastest version, on Hotspot 8, is:
MyClass[] arr = myList.toArray(new M...
Git Diff with Beyond Compare
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141
I don't use extra wrapper .sh files. My environment is Windows XP, git 1.7.1 on cygwin, and Bey...
Renaming columns in pandas
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1974
Just assign it to the .columns attribute:
>>> df = pd.DataFrame({'$a':[1,2], '$b': [10,...
'ssh-keygen' is not recognized as an internal or external command
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How do I tokenize a string in C++?
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Konrad RudolphKonrad Rudolph
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How to pass objects to functions in C++?
...able object.
– RC.
Jan 26 '10 at 12:43
20
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How do I capture the output of a script if it is being ran by the task scheduler?
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84
Try this as the command string in Task Scheduler:
cmd /c yourscript.cmd > logall.txt
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How to use if-else option in JSTL
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skaffmanskaffman
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