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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 = ...
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)
...
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
...
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
...
Need a simple explanation of the inject method
... |
edited Apr 2 '09 at 16:37
answered Apr 2 '09 at 16:31
Dr...
How do I calculate percentiles with python/numpy?
...centile() is available in numpy too.
import numpy as np
a = np.array([1,2,3,4,5])
p = np.percentile(a, 50) # return 50th percentile, e.g median.
print p
3.0
This ticket leads me to believe they won't be integrating percentile() into numpy anytime soon.
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Numpy: Divide each row by a vector element
...
answered Oct 26 '13 at 2:38
JoshAdelJoshAdel
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