[R] Dates

[gynmeerut]

Dear All,

I have a dataset containing Date column. I need to breakdown this dataset into two parts one which has datapoints before a particular date and the otherone on or after a particular date.

for example:
"2005-12-15",
"2008-12-14",
"2012-10-01",
"2009-11-15",
"2018-10-10",
"2014-08-31",
"2016-03-27",
"2010-01-01".
  say I want dates before  and after "2009-12-31"
that means I want ("2005-12-15","2008-12-14","2009-11-15")->x1
and ("2012-10-01","2018-10-10","2014-08-31","2016-03-27","2010-01-01")->x2


I wish to use different programs for these subsets.  
I could not find any way to compare dates with respect to some date.
Moreover dates are random I vary in no. So above is just an example.

  Any help will be appreciated.

regards,

GS