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r - 如何使用 case_when 从列表中删除元素

问题描述

我有一个嵌套的字符串列表，我想在满足 grepl 条件时在新列中输入一个值，并且我还想从嵌套列表中删除该元素

我的列表如下（嵌套在数据框中）

list( "Normal Mucosa Throughout", "Mitotic Lesion- See Text Above", 
    "Normal", 
    c("Mitotic", "Hiatus Hernia"), "Normal Mucosa Throughout", 
    "HALO RFA to Barrett's oesophagus", "Barretts oesophagus", 
    c("Barrett's oesophagus ", "EMR"))

期望的结果：

FindingsAfterProcessing                  DiagnosisCode             
Normal Mucosa Throughout                 other  
                                         C159
Normal                                   other
 Hiatus Hernia                           C159
Normal Mucosa Throughout                 other
HALO RFA to Barrett's oesophagus         other
Barretts oesophagus                      other
Barrett's oesophagus                     other
                                         EMR

我的case_when

 myDf<-myDf%>%   
    mutate(DiagnosisCode             = case_when( 
        grepl("mitotic|emr",tolower(myDf$OriginalFindings),ignore.case=TRUE) ~  "C159  -  Malignant neoplasm oesophagus, unspecified - Oesophagus - unspecified",
        TRUE                      ~  "other")
    )

如何将此应用于嵌套列表并在找到后删除该元素？

标签： r

解决方案

尝试map从purrr（你也可以只加载tidyverse）：

library(tidyverse)

df %>%
  mutate(
    DiagnosisCode = map(
      FindingsAfterProcessing, ~ case_when(
        any(grepl("mitotic", tolower(.x))) ~ "C159",
        any(grepl("emr", tolower(.x))) ~ "EMR",
        TRUE ~ "other")
      ),
    FindingsAfterProcessing = map(
      FindingsAfterProcessing, ~ .x[!grepl("mitotic|emr", tolower(.x))]
      )
  )

这里的输出是：

           FindingsAfterProcessing DiagnosisCode
1         Normal Mucosa Throughout         other
2                                           C159
3                           Normal         other
4                    Hiatus Hernia          C159
5         Normal Mucosa Throughout         other
6 HALO RFA to Barrett's oesophagus         other
7              Barretts oesophagus         other
8            Barrett's oesophagus            EMR

这不是 100% 对应于您想要的输出，但我猜您的输出中有错字？

我这样说是因为我的输出是基于您提供的列表；我已经把它变成了一个数据框列：

df <- data.frame(FindingsAfterProcessing = I(list( "Normal Mucosa Throughout", "Mitotic Lesion- See Text Above", 
                                  "Normal", 
                                  c("Mitotic", "Hiatus Hernia"), "Normal Mucosa Throughout", 
                                  "HALO RFA to Barrett's oesophagus", "Barretts oesophagus", 
                                  c("Barrett's oesophagus ", "EMR"))))

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