Question

你能帮我通过保留十进制数将一个字符串列分成 7 列吗？

这是一个例子：

library(dplyr)
library(tidyr)
library(stringr)

x <- data.frame(Flat = c("2000M01  XZ ELDL U K EER 213.9", "2000M02  XY MLML O T RRE 255.6" , "2000M03  UY LEEE M P SSE 259.4" ))  
x %>% separate(Flat, c("A1","B2","C3","D4","E5","F6","Value")

输出为：

     A1   B2  C3   D4 E5 F6 Value
1 2000M01 XZ ELDL  U  K EER   213
2 2000M02 XY MLML  O  T RRE   255
3 2000M03 UY LEEE  M  P SSE   259
Warning message:
Expected 7 pieces. Additional pieces discarded in 3 rows [1, 2, 3].

而不是所需的输出：

   A1     B2 C3    D4 E5 F6   Value
1 2000M01 XZ ELDL  U  K EER   213.9
2 2000M02 XY MLML  O  T RRE   255.6
3 2000M03 UY LEEE  M  P SSE   259.4

我在单独的函数中尝试了许多 "sep = " 选项，但没有任何帮助。

谢谢，

约翰

Answer 1

将 sep 参数作为 separate 中的空格传递。还可以使用 convert = TRUE 将 Value 列自动更改为数字。

tidyr::separate(x, Flat, 
      c("A1","B2","C3","D4","E5","F6","Value"), sep = '\\s+', convert = TRUE)

#       A1 B2   C3 D4 E5  F6 Value
#1 2000M01 XZ ELDL  U  K EER 213.9
#2 2000M02 XY MLML  O  T RRE 255.6
#3 2000M03 UY LEEE  M  P SSE 259.4

Answer 2

我们可以在 base R 中使用 read.table

read.table(text = x$Flat, header = FALSE,
       col.names =c("A1","B2","C3","D4","E5","F6","Value"))
       A1 B2   C3 D4 E5  F6 Value
1 2000M01 XZ ELDL  U  K EER 213.9
2 2000M02 XY MLML  O  T RRE 255.6
3 2000M03 UY LEEE  M  P SSE 259.4

Answer 3

带有 data.table 的 tstrsplit 选项

type.convert(
    setDT(x)[, setNames(
        tstrsplit(Flat, "\\s+"),
        c("A1", "B2", "C3", "D4", "E5", "F6", "Value")
    )],
    as.is = TRUE
)

给出

        A1 B2   C3 D4 E5  F6 Value
1: 2000M01 XZ ELDL  U  K EER 213.9
2: 2000M02 XY MLML  O  T RRE 255.6
3: 2000M03 UY LEEE  M  P SSE 259.4

Answer 4

这当然不像亲爱的@akrun 那样出色，但它也能解决问题：

library(tidyr)

x %>%
  extract(Flat, c("A1","B2","C3","D4","E5","F6","Value"), 
          "(\\d+M\\d+)  ([[:upper:]]+) ([[:upper:]]+) ([[:upper:]]) ([[:upper:]]+) ([[:upper:]]+) (\\d+\\.\\d)")

       A1 B2   C3 D4 E5  F6 Value
1 2000M01 XZ ELDL  U  K EER 213.9
2 2000M02 XY MLML  O  T RRE 255.6
3 2000M03 UY LEEE  M  P SSE 259.4

Answer 5

data.table 路

library(data.table)
ans <- data.table()[,c("A1","B2","C3","D4","E5","F6","Value") := tstrsplit(x$Flat, "[ ]+")]
#         A1 B2   C3 D4 E5  F6 Value
# 1: 2000M01 XZ ELDL  U  K EER 213.9
# 2: 2000M02 XY MLML  O  T RRE 255.6
# 3: 2000M03 UY LEEE  M  P SSE 259.4

R 如何分隔基于字符串的空格但保留小数点？

5 个答案: