从其他数据中获取最高水平的值

Question

Suppose I have data including some information of names and scores in school.

name = c('Ann','Dann','Pann', 'Sam', 'Lora', 'Peter')
score = c(30,30,50,70,20,10)
school = data.frame(name=name, score=score)

I may use 'which.max' to find the highest level of the data.

data = school[which.max(school$score),]
data$name
[1] Sam

Now I want to find the name with the highest score in Aclass set.

Aclass = c('Peter','Pann', 'Lora', 'Smith')

The outcome should be

[1] 'Pann'

Please notice 'Smith' is not a part of school data. Regardless of how many new names are included in Aclass, what I want to find is just a name with the highest score in school data. What code should I make to get it?

Answer 1

This method searches through a subset of the data.frame school using with to reduce typing.

with(school[school$name %in% Aclass,], name[which.max(score)])

[1] Pann
Levels: Ann Dann Lora Pann Peter Sam