如何汇总列中的响应以根据列标题创建新响应？答案

【问题标题】：How to summarize responses in column to create a new response based on column headers?如何汇总列中的响应以根据列标题创建新响应？
【发布时间】：2023-01-07 03:44:58
【问题描述】：

我的数据看起来像这样

ID<- c(1,2,3,4,5)
CV<- c("Detected", "Not Detected", "Detected", "Not Detected", "Detected")
RV<- c("Not Detected", "Detected", "Not Detected", "Detected", "Not Detected")
BP<- c("Detected", "Detected", "Not Detected", "Detected", "Detected")
FL<- c("Detected", "Detected", "Not Detected", "Detected", "Detected")

df<- data.frame(ID, CV, RV, BP, FL)

我想结合每个观察中的“检测到”响应并创建一个新列，给出每个检测到的响应的列名，就像这样

ID          CV                RV               BP              FL             Result
1           Detected          Not Detected     Detected        Detected       CV, BP, FL
2           Not Detected      Detected         Detected        Detected       RV, BP, FL
3           Detected          Not Detected     Not Detected    Not Detected   CV
4           Not Detected      Detected         Detected        Detected       RV, BP, FL
5           Detected          Not Detected     Detected        Detected       CV, BP, FL

【问题讨论】：

标签： r if-statement dplyr tidyverse multiple-columns

【解决方案1】：

在base R中使用apply

df$Result <- apply(df[-1], 1, (x) toString(names(x)[x == "Detected"]))

-输出

> df
  ID           CV           RV           BP           FL     Result
1  1     Detected Not Detected     Detected     Detected CV, BP, FL
2  2 Not Detected     Detected     Detected     Detected RV, BP, FL
3  3     Detected Not Detected Not Detected Not Detected         CV
4  4 Not Detected     Detected     Detected     Detected RV, BP, FL
5  5     Detected Not Detected     Detected     Detected CV, BP, FL

【讨论】：

【解决方案2】：

library(dplyr)
library(tidyr)

df %>% 
  mutate(across(-ID, ~case_when(. == "Detected" ~ cur_column()), .names = 'new_{col}')) %>%
  unite(Result, starts_with('new'), na.rm = TRUE, sep = ' ')

  ID           CV           RV           BP           FL   Result
1  1     Detected Not Detected     Detected     Detected CV BP FL
2  2 Not Detected     Detected     Detected     Detected RV BP FL
3  3     Detected Not Detected Not Detected Not Detected       CV
4  4 Not Detected     Detected     Detected     Detected RV BP FL
5  5     Detected Not Detected     Detected     Detected CV BP FL

【讨论】：