在R中，如何创建一个变量，其内容基于其他变量中的内容？

我有一个数据集，其中包含治疗列表（治疗变量），然后另一个人根据其作用机制（机制变量）对这些治疗进行分类。我想添加另一种作用机制类别（体温过低），我正在努力这样做

我制作了一个小数据框，作为一些治疗方法及其机制类别的示例

Treatment <- c("Hypothermia", "CNS-1102", "Hypocapnia", "Dextrorphan", "Mannitol", "Caffeinol")
Mechanism <- c("Other", "Excitotoxicity", "Blood flow", "Excitotoxicity", "Fluid regulation", "Other")
df <- data.frame(Treatment, Mechanism)

---

Treatment您可以使用
dplyr
将其设置为
tibble
而不是
data.frame
，这将起作用

library(dplyr)

Treatment <- c("Hypothermia", "CNS-1102", "Hypocapnia", "Dextrorphan", "Mannitol", "Caffeinol")
Mechanism <- c("Other", "Excitotoxicity", "Blood flow", "Excitotoxicity", "Fluid regulation", "Other")
df <- tibble(Treatment, Mechanism) # changed this


df %>% 
  mutate(Mechanism_extra = if_else(Treatment == "Hypothermia", "Hypothermia", Mechanism))

库（dplyr）
处理使您的数据成为字符，它们现在是因素。在您的示例中，您可以执行
df，也可以将R版本升级到4.0
stringsAsFactors=FALSE现在是默认值。非常感谢！我真后悔解决办法这么简单！我想我现在应该开始一直使用tibbles。。。
library(dplyr)

Treatment <- c("Hypothermia", "CNS-1102", "Hypocapnia", "Dextrorphan", "Mannitol", "Caffeinol")
Mechanism <- c("Other", "Excitotoxicity", "Blood flow", "Excitotoxicity", "Fluid regulation", "Other")
df <- tibble(Treatment, Mechanism) # changed this


df %>% 
  mutate(Mechanism_extra = if_else(Treatment == "Hypothermia", "Hypothermia", Mechanism))

# A tibble: 6 x 3
  Treatment   Mechanism        Mechanism_extra 
  <chr>       <chr>            <chr>           
1 Hypothermia Other            Hypothermia     
2 CNS-1102    Excitotoxicity   Excitotoxicity  
3 Hypocapnia  Blood flow       Blood flow      
4 Dextrorphan Excitotoxicity   Excitotoxicity  
5 Mannitol    Fluid regulation Fluid regulation
6 Caffeinol   Other            Other