I know max(diamonds$price) is the way to find the price of the most expensive one. I do not know how to find its weight

CodePudding user response：

diamonds$weight[diamonds$price == max(diamonds$price)]

Meaning, extract vector weight from data.frame diamonds, filtering at the rows where price is equal to the max price.

CodePudding user response：

> df <- data.frame(price = c(1, 2, 3), 
                   weight = c(10, 5, 2))

> df
  price weight
1     1     10
2     2      5
3     3      2

> df[which.max(df$price), ]$weight
[1] 2