[R] Create a data.table by looping over variable names

[David Käthner]

Maybe there’s a cleverer way, but that’s what I can think off the top of my head:

n <- 100
M.dt <- data.table(matrix(ncol = 100))
M.dt[] <- 100
names(M.dt) <- sapply(1:100, function(x) paste0("i", x))

The sapply is your loop.

> Am 16.12.2015 um 12:53 schrieb Matteo Richiardi <matteo.richiardi at gmail.com>:
> 
> I apologise for this very basic question, but I found no answers on the web.
> I want to create a data.table with n columns, named i1 ... i'n', with only
> one row with value = 100 for every variable.
> 
> I can do it "by hand":
> 
> M.dt <- data.table(i1=100,i2=100,i3=100)
> 
> but I would like to make it in a loop, as 'n' is large in my case.
> 
> 
> Thanks.
> 
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> 
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