匹配函数重复值

Question

我想知道R中是否有函数可以帮助我处理问题匹配函数，如果两个数据集有重复值会创建吗？

例如，

x=c(1,2,2,3,3)
y=c(2,2,3)

我希望将所有2,2,3,3保留在X中，但只列出Y中的2,2,3，我仍然希望它们按顺序排列。

有办法吗？

Answer 1

    x[which(x %in% y)]
    y[which(y %in% x)]

Answer 2

#crate some objects to match
x<-data.frame(fruits = c("apples", "bananas", "oranges", "apples"), values = c(1,2,3,4))
y<-data.frame(fruits = c("apples", "oranges", "bananas"), colors = c("red", "pink", "green" )
# x$color will be the new column in x with relevant values from y
# ifelse is a simple condition - if a fruit is found in y, it gets the color from y, if there is nothing to match, it gets an NA 
x$color<-ifelse(x$fruits %in% y$fruits,as.character(y$colors), NA)
x