Turn vector output into columns in data.table?

data.table, r

Solution

Try

data[, as.list(foo(args)), by=list(Year, Month)]

or change `foo` to return a `list` rather than a `vector`.

Problem

I am generating output by applying function to some subsets of data.table. I am using function like this: ``` data[, foo(args), by=list(Year, Month)] ``` My function `foo` return always a vector of length `n`. I am getting an output like this: ``` Year Month V1 1: 1983 2 9.734669e-06 2: 1983 2 9.165665e-06 3: 1983 2 2.097477e-05 4: 1983 2 3.803727e-05 ``` But I would like something like ``` Year Month V1 V2 V3 V4 ... 1: 1983 2 9.734669e-06 9.165665e-06 2.097477e-05 3.803727e-05 ... ``` I even tried using `list(foo(args))`, it didn't help. Or should the output be in form `foo$V1, foo$V2 ...`?

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