>> aggregate(dat$value, list(dat$x, dat$y), mean)
> Group.1 Group.2 x
> 1 1 1 15
> 2 1 2 30
>> newdat <-aggregate(dat$value, list(dat$x, dat$y), mean)
>> names(newdat) <- c("x","y",bquote("mean(value)") )
That bquote isn't necessary because you're already working with strings.
c(x = 1, y = 2, "mean(value)" = 3)
Hadley
--
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