R编程: perform function with switch functionality for each row based on different columns

Question

在 R 编程中，我尝试执行以下操作:

    df
    A       B     Category
    0.9     0.85  A
    0.7     0.75  B
    0.8     0.90  B

    CSF <- function(df, type) {
    switch(type,
               "A" = qnorm(df$A, 0 , 1),
               "B" = qnorm(df$B, 0 , 1)
    )
    }

    df<-data.frame(df, value = CSF(df,df$category))

期望的结果:

    df
    A       B     Category     Value
    0.9     0.85  A            qnorm(0.9, 0, 1)*
    0.7     0.75  B            qnorm(0.75, 0, 1)*
    0.8     0.90  B            qnorm(0.9, 0, 1)*

*:真实值

错误信息:EXPR 必须是长度为 1 的向量

Answer 1

你可以使用ifelse函数:

df$Value <- ifelse(df$Category=="A",qnorm(df$A,0,1),qnorm(df$B,0,1))