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Why are C character literals ints instead of chars?
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answered Apr 23 '14 at 16:04
John VincentJohn Vincent
57155 silver badges44 bronze badges
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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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了解 Boost Filesystem Library - C/C++ - 清泛网 - 专注C/C++及内核技术
...例程。此代码经过验证，能在不用修改的情况下在 gcc-3.4.4 和 cl-13.10.3077 上成功编译。
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了解 Boost path 对象
了解 Boost Filesystem Library 的关键是 path 对象，因为 Filesystem Library 中定义的多个例程都要对相应的 path 对象操作...
How do I tokenize a string in C++?
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Konrad RudolphKonrad Rudolph
461k117117 gold badges863863 silver badges11101110 bronze badges
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How to pass objects to functions in C++?
...able object.
– RC.
Jan 26 '10 at 12:43
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