如何提取R'的结果；s strsplit（）

问题:

我有一个字符串向量foo：

>foo = c("1x2","3x4","5x6","7x8","9x10")

我将单个字符串拆分到“x”上，并将结果粘贴到goo中：

>goo = strsplit(foo, "x")
>goo
[[1]]
[1] "1" "2"

[[2]]
[1] "3" "4"

[[3]]
[1] "5" "6"

[[4]]
[1] "7" "8"

[[5]]
[1] "9"  "10"

---

如何从列表中提取第一列和第二列？（我想要（1,3,5,7,9）和（2,4,6,8,10））

使用

sapply

使用“[]”连续“提取”：

---

我一直认为这应该是结果，但我可能不理解问题所在。

使用

sapply

使用“[[””连续“提取”：

---

我一直认为这应该是结果，但我可能不理解问题所在。

最简单的方法是将结果包装在一个

精辟的
语句中

odd_results <- sapply(goo, function(x) x[1])

odd_results最简单的方法是将结果包装在
sapply
语句中

odd_results <- sapply(goo, function(x) x[1])

odd_结果概述
您需要指定按位置提取列表元素

# load data
foo <- c("1x2","3x4","5x6","7x8","9x10")

# split foo by 'x'
foo.list <- strsplit( x = foo, split = "x", fixed = TRUE )

# store the first and second elements of each list in a data frame
foo.df <-
data.frame(
    First_Element = unlist( lapply( X = foo.list, FUN = "[[", FUN.VALUE = 1 ) )
    , Second_Element = unlist( lapply( X = foo.list, FUN = "[[", FUN.VALUE = 2 ) )
  )

#加载数据
foo概述
您需要指定按位置提取列表元素

# load data
foo <- c("1x2","3x4","5x6","7x8","9x10")

# split foo by 'x'
foo.list <- strsplit( x = foo, split = "x", fixed = TRUE )

# store the first and second elements of each list in a data frame
foo.df <-
data.frame(
    First_Element = unlist( lapply( X = foo.list, FUN = "[[", FUN.VALUE = 1 ) )
    , Second_Element = unlist( lapply( X = foo.list, FUN = "[[", FUN.VALUE = 2 ) )
  )

#加载数据
foo为了多样性，你可以使用

goo <- unlist(strsplit(foo, "x"))

a <- goo[seq(1, length(goo), 2)]
b <- goo[seq(2, length(goo), 2)]

及

分别。
为了多样性，您可以使用

goo <- unlist(strsplit(foo, "x"))

a <- goo[seq(1, length(goo), 2)]
b <- goo[seq(2, length(goo), 2)]

> result <-  do.call(rbind, goo)
> result
     [,1] [,2]
[1,] "1"  "2" 
[2,] "3"  "4" 
[3,] "5"  "6" 
[4,] "7"  "8" 
[5,] "9"  "10"
> result[, 1] # column 1
[1] "1" "3" "5" "7" "9"
> result[, 2] # column 2
[1] "2"  "4"  "6"  "8"  "10"

及

分别。
>结果
> result <-  do.call(rbind, goo)
> result
     [,1] [,2]
[1,] "1"  "2" 
[2,] "3"  "4" 
[3,] "5"  "6" 
[4,] "7"  "8" 
[5,] "9"  "10"
> result[, 1] # column 1
[1] "1" "3" "5" "7" "9"
> result[, 2] # column 2
[1] "2"  "4"  "6"  "8"  "10"

[,1] [,2]
[1,] "1"  "2" 
[2,] "3"  "4" 
[3,] "5"  "6" 
[4,] "7"  "8" 
[5,] "9"  "10"
>结果[，1]#第1列
[1] "1" "3" "5" "7" "9"
>结果[，2]#第2列
[1] "2"  "4"  "6"  "8"  "10"
>结果
[,1] [,2]
[1,] "1"  "2" 
[2,] "3"  "4" 
[3,] "5"  "6" 
[4,] "7"  "8" 
[5,] "9"  "10"
>结果[，1]#第1列
[1] "1" "3" "5" "7" "9"
>结果[，2]#第2列
[1] "2"  "4"  "6"  "8"  "10"
sappy（goo，identity）
然后切片行。
read.table（text=foo，sep='x'）[，1]
sappy（goo，identity）
然后切片行。
read.table（text=foo，sep='x'）[，1]