Question

我在从data.frame获取所需的输出时遇到问题。数据的结构如下：

head(test)

    A  T  L   B  E  X   D
4  no no no yes no no yes
7  no no no  no no no  no
11 no no no  no no no  no
12 no no no yes no no yes
17 no no no  no no no  no
27 no no no  no no no  no

我得到的输出：

test[1,]
   A  T  L   B  E  X   D
4 no no no yes no no yes

我想要的输出：

[1] "no"  "no"  "no"  "yes" "no"  "no"  "yes"

或者简单地说，我想要的输出是一个向量，其中每个元素都是df中该列的字符串值。我可以进行for循环或类似的愚蠢操作，但我相信应该缺少一种更简单的方法。

我尝试过：

as.character(test[1,])
[1] "1" "1" "1" "2" "1" "1" "2"

不确定我在这里想念什么吗？

Answer 1

使用unlist，然后使用as.character

as.character(unlist(test[1, ]))
#[1] "no"  "no"  "no"  "yes" "no"  "no"  "yes"

test[1, ]仍然是数据帧，并且在数据帧上应用as.character无效。我们使用unlist将数据帧转换为矢量，然后使用as.character将其转换为字符。

数据

test <- structure(list(A = structure(c(1L, 1L, 1L, 1L, 1L, 1L), .Label = "no", class = "factor"), 
T = structure(c(1L, 1L, 1L, 1L, 1L, 1L), .Label = "no", class = "factor"), 
L = structure(c(1L, 1L, 1L, 1L, 1L, 1L), .Label = "no", class = "factor"), 
B = structure(c(2L, 1L, 1L, 2L, 1L, 1L), .Label = c("no", 
"yes"), class = "factor"), E = structure(c(1L, 1L, 1L, 1L, 
1L, 1L), .Label = "no", class = "factor"), X = structure(c(1L, 
1L, 1L, 1L, 1L, 1L), .Label = "no", class = "factor"), D = structure(c(2L, 
1L, 1L, 2L, 1L, 1L), .Label = c("no", "yes"), class = "factor")), 
class = "data.frame", row.names = c("4", "7", "11", "12", "17", "27"))

在data.frame中获取一行作为向量，其中每个元素都是一个字符串

1 个答案: