[R] how to expand the dataframe

[Jeff Newmiller]

Look at the zoo or data.table packages. 
-- 
Sent from my phone. Please excuse my brevity.

On July 20, 2016 1:31:26 PM PDT, lily li <chocold12 at gmail.com> wrote:
>Hi R users,
>
>I have a dataframe, where there is a column 'time' represents time
>series
>but is not complete. How to expand the dataframe so this column will
>become
>complete, where other columns with the newly added rows have NA values?
>Thanks.
>
>df
>A     B     C     time
>10    5     3.3   1990-01-01
>11    5      4     1990-02-07
>12    4     3      1990-02-14
>...
>
>	[[alternative HTML version deleted]]
>
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