Create an r data.table with a date formatted column -

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i'm trying create data.table date/time formatted column populated in next steps. i've tried bunch of different functions can't find 1 package wants.

see column3 in below examples:

require(data.table) num_rows <- 5 dt <- data.table(column1 = character(num_rows),                  column2 = integer(num_rows),                  column3 = date(num_rows)                  )  dt <- data.table(column1 = character(num_rows),                  column2 = integer(num_rows),                  column3 = posixct(num_rows)                  )  dt <- data.table(column1 = character(num_rows),                  column2 = integer(num_rows),                  column3 = idatetime(num_rows)                  )

what function creates date or time column in data.table? can't find anywhere.

cheers.

note integer(num_rows) makes vector of 0s, character(num_rows) makes vector of ""s etc.

so initialise dates value, e.g.

column3=rep(sys.time(), num_rows) # posixct

or

column3=rep(sys.date(), 3) # date

i'd recommend initialising default date/datetime makes sense application (e.g. column2 initialised 0 , column1 initialised ""). maybe default origin value e.g. 1970-01-01 00:00 (column3=rep(as.posixct('1970-01-01 00:00'), num_rows))


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