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How do I make a matrix from a list of vectors in R?
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124
One option is to use do.call():
> do.call(rbind, a)
[,1] [,2] [,3] [,4] [,5] [,6]
[...
What is the best regular expression to check if a string is a valid URL?
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415
I wrote my URL (actually IRI, internationalized) pattern to comply with RFC 3987 (http://www.f...
Concatenating two one-dimensional NumPy arrays
... explicit sequences).
– Jim K.
Aug 24 '16 at 20:43
@JimK. What would happen to the axis parameter?
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Split a vector into chunks in R
...(), split() and ceiling():
> d <- rpois(73,5)
> d
[1] 3 1 11 4 1 2 3 2 4 10 10 2 7 4 6 6 2 1 1 2 3 8 3 10 7 4
[27] 3 4 4 1 1 7 2 4 6 0 5 7 4 6 8 4 7 12 4 6 8 4 2 7 6 5
[53] 4 5 4 5 5 8 7 7 7 6 2 4 3 3 8 11 6 6 1 8 4
> m...
C++并发编程（中文版） - 文档下载 - 清泛网 - 专注C/C++及内核技术
...的并发… 1
1.1.2 并发的方法… 3
1.2 为什么使用并发… 4
1.2.1 因划分重点而使用并发… 5
1.2.2 为了提高性能而使用并发… 5
1.2.3 什么时候不使用并发… 6
1.3 在C++中使用并发和多线程… 7
1.3.1 多线程在C++中的发展历程… 7
1.3.2...
Remove duplicate elements from array in Ruby
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edited May 20 at 4:57
the Tin Man
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Applying a function to every row of a table using dplyr?
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answered Jul 14 '14 at 0:20
alexwhanalexwhan
13.8k55 gold badges4545 silver badges6464 bronze badges
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Filter rows which contain a certain string
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4 Answers
4
Active
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Can dplyr package be used for conditional mutating?
...f %>%
mutate(g = ifelse(a == 2 | a == 5 | a == 7 | (a == 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; howev...