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How to select the row with the maximum value in each group
...t]$V1]
# Subject pt Event
# 1: 1 5 2
# 2: 2 17 2
# 3: 3 5 2
If you'd like just the first max value of pt:
group[group[, .I[which.max(pt)], by=Subject]$V1]
# Subject pt Event
# 1: 1 5 2
# 2: 2 17 2
# 3: 3 5 2
In this case, it ...
Split delimited strings in a column and insert as new rows [duplicate]
...her way of doing it..
df <- read.table(textConnection("1|a,b,c\n2|a,c\n3|b,d\n4|e,f"), header = F, sep = "|", stringsAsFactors = F)
df
## V1 V2
## 1 1 a,b,c
## 2 2 a,c
## 3 3 b,d
## 4 4 e,f
s <- strsplit(df$V2, split = ",")
data.frame(V1 = rep(df$V1, sapply(s, length)), V2 = ...
do N times (declarative syntax)
..., without any library, just native vanilla.
To basically call something() 3 times, use:
[1,2,3].forEach(function(i) {
something();
});
considering the following function:
function something(){ console.log('something') }
The outpout will be
something
something
something
To complete thi...
Optional Parameters with C++ Macros
...S(message, size) PrintString(message, size, 0)
#define PRINT_STRING_3_ARGS(message, size, style) PrintString(message, size, style)
#define GET_4TH_ARG(arg1, arg2, arg3, arg4, ...) arg4
#define PRINT_STRING_MACRO_CHOOSER(...) \
GET_4TH_ARG(__VA_ARGS__, PRINT_STRING_3_ARGS, \
...
莱昂氏unix源代码分析 PDF - 文档下载 - 清泛网 - 专注C/C++及内核技术
...篇 UNIX操作系统版本6源代码
UNIX操作系统过程分类索引 3
UNIX操作系统文件及过程 5
UNIX操作系统定义的符号列表 7
UNIX操作系统源代码交叉引用列表 9
第一部分 初始化、进程初始化 25
第二部分 陷入、中断、系统调用和
...
Using python map and other functional tools
...ferent functions, but to access it directly from maptest:
foos = [1.0,2.0,3.0,4.0,5.0]
bars = [1,2,3]
def maptest(foo):
print foo, bars
map(maptest, foos)
With your original maptest function you could also use a lambda function in map:
map((lambda foo: maptest(foo, bars)), foos)
...
Printing tuple with string formatting in Python
So, i have this problem.
I got tuple (1,2,3) which i should print with string formatting.
eg.
14 Answers
...
Removing projects in Sublime Text 2 and 3
How do you remove a project from Sublime Text 2 and 3's project windows ( Ctrl + Alt + P ) ?
5 Answers
...
How to install therubyracer gem on 10.10 Yosemite?
...8
bundle install
bundle exec rake clean build binary
gem install pkg/libv8-3.16.14.3-x86_64-darwin-12.gem #note that libv8 version may change, so tab through files in pkg/, also remember to use the one with version specified
then just bundle your project gems
this is the only way it worked for me...
Can dplyr package be used for conditional mutating?
... 1 & b == 4), 2,
ifelse(a == 0 | a == 1 | a == 4 | a == 3 | c == 4, 3, NA)))
Added - if_else: Note that in dplyr 0.5 there is an if_else function defined so an alternative would be to replace ifelse with if_else; however, note that since if_else is stricter than ifelse (both leg...