r - 将 stringr str_detect 管道传输到 str_extract 时出现问题 - extract 仅从第一行提取文本 : argument is not an atomic vector; coercing

Question

我正在尝试创建一个新列，其中仅包含表达式中的某些数字数据。

这是我的数据:https://pastebin.com/hYg3zqYz

我只需要第 12 列中“双极”之后的数字。

这是有效的

p <- df %>% 
      select(where(~ any(stringr::str_detect(.x, "Bipolar")))) #returns correct column

当我尝试创建一个仅提取文本的新列时，它只返回第一行，不确定我做错了什么。

p %>%
      mutate(group = "sr_bipol",
             sr_bipol = as.numeric(stringr::str_extract(., "[0-9].[0-9]+"))) %>% 
       select(group, sr_bipol)

# A tibble: 20 × 2
   group    sr_bipol
   <chr>       <dbl>
 1 sr_bipol     7.83
 2 sr_bipol     7.83
 3 sr_bipol     7.83
 4 sr_bipol     7.83
 5 sr_bipol     7.83
.....................

我还收到错误代码:

 argument is not an atomic vector; coercing 

加载新案例后，我尝试使用以下解决方案，但遇到了新错误

新数据:https://paste.kodi.tv/azuramoguh

df %>% 
  transmute(across(where(~ any(stringr::str_detect(.x, "Bipolar"))), 
   ~ as.numeric(str_extract(.x, "(?<=Bipolar\\s)[0-9]\\.[0-9]+")), 
     .names = "sr_bipol{str_remove(.col, '[.]+')}"))

Error in `$<-.data.frame`(`*tmp*`, "call_text", value = c("df %>% ...",  : 
  replacement has 13 rows, data has 12

还尝试过:

df %>% 
  select(where(~ any(stringr::str_detect(.x, "Bipolar")))) %>% #this finds the column with the bipolar ##voltage data
  transmute(group = "sr_bipol",
            sr_bipol = as.numeric(
              stringr::str_extract(pull(.,1), "[0-9].[0-9]+") #str_extract expects a vector, so "pull" to #change from df to vector
              )
            ) %>%
  bind_cols(carto_lv_sr_volt %>% select(x:z))

Error in `select()`:
! `where()` must be used with functions that return `TRUE` or `FALSE`.

Answer 1

.指整个数据集( str_extract 需要一个向量作为输入，而不是 data.frame)。根据?str_extract

string - Input vector. Either a character vector, or something coercible to one.

我们可能需要申请str_extract在列 12 上。作为 12 前缀的列名称，包括 ...这是不常见的列名称，请使用反引号来访问列值

library(dplyr)
library(stringr)
df %>% 
  transmute(group = 'sr_bipol', 
    sr_bipol = as.numeric(str_extract(`...12`, "(?<=Bipolar\\s)[0-9]\\.[0-9]+")))

-输出

# A tibble: 20 × 2
   group    sr_bipol
   <chr>       <dbl>
 1 sr_bipol     7.83
 2 sr_bipol     2.34
 3 sr_bipol     1.97
 4 sr_bipol     1.94
 5 sr_bipol     2.85
 6 sr_bipol     2.92
 7 sr_bipol     3.05
 8 sr_bipol     2.80
 9 sr_bipol     3.43
10 sr_bipol     2.11
11 sr_bipol     2.80
12 sr_bipol     1.81
13 sr_bipol     1.84
14 sr_bipol     3.87
15 sr_bipol     1.68
16 sr_bipol     2.21
17 sr_bipol     2.97
18 sr_bipol     3.09
19 sr_bipol     2.84
20 sr_bipol     3.48

---

p数据是单列tibble/data.frame 。当我们使用.时，它选择 data.frame，即

> str(p)
tibble [20 × 1] (S3: tbl_df/tbl/data.frame)
 $ ...12: chr [1:20] "Bipolar 7.827 / Unipolar 16.911 / LAT -9.0" "Bipolar 2.34 / Unipolar 9.09 / LAT -10.0" "Bipolar 1.974 / Unipolar 9.219 / LAT -11.0" "Bipolar 1.938 / Unipolar 10.572 / LAT -9.0" ...
> str_extract(p, "[0-9].[0-9]+")
[1] "7.827"
Warning message:
In stri_extract_first_regex(string, pattern, opts_regex = opts(pattern)) :
  argument is not an atomic vector; coercing

它从第一个实例中提取值，并回收该值以创建 7.8 的整个列

---

如果有多个列具有“双极性”，我们可以循环across (如果我们想保留原始数据中的所有其他列，请将 transmute 修改为 mutate)

df %>% 
  transmute(across(where(~ any(stringr::str_detect(.x, "Bipolar"), na.rm = TRUE)), 
   ~ as.numeric(str_extract(.x, "(?<=Bipolar\\s)[0-9]\\.[0-9]+")), 
     .names = "sr_bipol{str_remove(.col, '[.]+')}"))
# A tibble: 20 × 1
   sr_bipol12
        <dbl>
 1       7.83
 2       2.34
 3       1.97
 4       1.94
 5       2.85
 6       2.92
 7       3.05
 8       2.80
 9       3.43
10       2.11
11       2.80
12       1.81
13       1.84
14       3.87
15       1.68
16       2.21
17       2.97
18       3.09
19       2.84
20       3.48