Mean of a column in a data frame, given the column's name

Question

I\'m inside a big function I have to write. In the last part I have to calculate the mean of a column in a data frame. The name of the column I am operating on is given as a

Answer 1

Any of the following should work!!

df <- data.frame(x=1:3,y=4:6)

mean(df$x)
mean(df[,1])
mean(df[["x"]])