I read that data.table understands the dot "." as an alias of "list". But:
> dt <- data.table(x = c(11, 22), y = c("f", "b"))
> dt
x y
1: 11 f
2: 22 b
> dt[,.(y)]
Error in eval(expr, envir, enclos) : could not find function "."
>
Why is that?
According to the data.table New features on v.1.9.4
( https://github.com/Rdatatable/data.table ),
.() can now be used in j and is identical to list(), for consistency with i.
So, it is better to install either v.1.9.4
version or the devel version from here
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