Question

我有两个数据帧（df1，df2）。我想在df2中创建一个新的“分数”列，该列将遵循ifelse语句。

If Else Statement:
If pn1=pn2 & sub1=sub2, then score = 2, 
elseif pn1=pn2 & sub1 IS IN sub2, then score = 1, 
elseif pn=pn, then score = 0,
else score = NA. 
```
    pn1 <- c('12345','12345','13579', '01289','22468')

    sub1 <- c('01','x001','hi-02','bye','12')

    pn2 <- c('12345','12345','13579', '01289','22468','28245')

    sub2 <- c('01','x002','hi-2','b','xyz','23')

    row <-c(1,2,3,4,5,6)

    df1 <- data.frame(pn1,sub1)

    df2 <- data.frame(row,pn2,sub2)

    #Desired Output 
    score <- c(2,1,1,1,0,'NA')

    df2$score <- score
```
For further explanation on the if statement:
Row 1- Score = 2 because PN1 = PN2 and SUB1=SUB2.
Row 2,3,4- Score = 1 because PN1 = PN2 and SUB1 can be found in SUB2.
Row 5- Score = 0 because PN1=PN2.
Row 6- Score = NA because PN2 is not found in df1.

Answer 1

由于两个数据框的尺寸不同，因此我无法完全理解您的问题。另外，在您的示例中，在这些情况下，第二到第四个索引不会评估为1，因为SUB1不在SUB2中。该答案基于您描述的所需内容，而不是您认为想要的内容。

df1 <- data.frame(pn1,sub1, stringsAsFactors = FALSE)
df2 <- data.frame(row,pn2,sub2, stringsAsFactors = FALSE)
library(dplyr)
df2$score <- case_when(df2$pn2 == df1$pn1 & df2$sub2 == df1$sub1 ~ 2,
                       df2$pn2 %in% df1$pn1 & df2$sub2 %in% df1$sub1 ~ 1,
                       df2$pn2 %in% df1$pn1 & !(df2$sub2 %in% df1$sub1) ~ 0,
                       !(df2$pn2 %in% df1$pn1) ~ NA_real_)

如何使用if else语句创建关于来自两个不同数据帧的两个列的新列？

1 个答案: