Question

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我有三列。患者姓名，是否有抗生素，以及抗生素的品牌。然而，有时我会从＃34; Antibiotics＆＃34;但是我在第三栏中注意到他们说他们得了抗生素，因为他们收到的品牌并不算数。

df<-data.frame(Names=c("Patient1","patient2","Patient3","Patient4","patient5"),Antibiotics=c("Y","N","Y","","Y"), TypeAntibiotic=c("","","BrandA",,"BrandA",""))

我想有条件地填补＆＃34; Antibiotics＆＃34;如果第三栏有＆＃34; BrandA＆＃34;。但是，如果已经有了某些东西，那么我就不想这样做了。抗生素＆＃34;

我知道：

    df%>%mutate(Antibiotics=ifelse(grepl("BrandA",TypeAntibiotic),"N",Antibiotics))

会给我一个＆＃34; N＆＃34;在我想要的专栏中，但我相信它会覆盖我已经拥有的任何＆＃34; Y＆＃34; s。我怎么只放一个＆＃34; N＆＃34;如果那行中还没有东西？

Answer 1

这是基础R解决方案

myindex=df$Antibiotics==""&df$TypeAntibiotic=="BrandA"
df$Antibiotics[myindex]="N"

Answer 2

我相信这可能就是你要找的东西，

df<-data.frame(Names=c("Patient1","patient2","Patient3","Patient4","patient5"),Antibiotics=c("Y","N","Y","","Y"), TypeAntibiotic=c("","","BrandA","BrandA",""), stringsAsFactors = FALSE)

df$Antibiotics <- ifelse((df$Antibiotics == "") & (df$TypeAntibiotic == "BrandA"),
                         "N", df$Antibiotics

请注意，我稍微修改了df的定义，以便变量不是因子。

如果你想使用你已经拥有的代码，你只需要

df%>%mutate(Antibiotics=ifelse(grepl("BrandA",TypeAntibiotic) & df$Antibiotics == "","N",Antibiotics))

Answer 3

df$Antibiotics[df$Antibiotics=="" & df$TypeAntibiotic=="BrandA"]<-"N"

哦，我看到@Antonis给了同样的解决方案......

Answer 4

data.table解决方案

library(data.table)
df<-as.data.table(df)
df[Antibiotics=="" & TypeAntibiotic=="BrandA",Antibiotics:='N']

在两个不同的列上有条件地填充列值

4 个答案: