[R] adding elemens to a list

[antonio rodriguez]

Hi,

I have a list of 20 elements, each of them of variable length and with a 
structure like this:

lasker[[1]][1:10,]

         Var1 Freq
1  1988-02    3
2  1988-03    1
3  1988-04    1
4  1988-05    2
5  1988-06    3
6  1988-07    1
7  1988-08    1
8  1988-09    1
9  1989-03    1
10 1989-04    1

How do I can insert in this list:

1988-01   0
1988-10   0
1988-11   0
1988-12   0
1989-01   0
1989-02   0

It's to say, the appropiate missing Year-Month row equal 0

Antonio

PD: follows dput output of lasker[[1]]

dput(lasker[[1]],control="all")
structure(list(Var1 = structure(as.integer(c(1, 2, 3, 4, 5, 6,
7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22,
23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38,
39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54,
55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70,
71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86,
87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101,
102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114,
115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127,
128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140,
141, 142, 143, 144, 145, 146, 147, 148, 149, 150, 151, 152, 153,
154, 155, 156, 157, 158, 159, 160, 161, 162, 163, 164, 165, 166,
167, 168, 169, 170)), .Label = c("1988-02", "1988-03", "1988-04",
"1988-05", "1988-06", "1988-07", "1988-08", "1988-09", "1989-03",
"1989-04", "1989-05", "1989-07", "1989-08", "1989-09", "1989-11",
"1990-01", "1990-02", "1990-03", "1990-04", "1990-05", "1990-06",
"1990-07", "1990-08", "1990-10", "1990-11", "1991-01", "1991-03",
"1991-04", "1991-05", "1991-06", "1991-09", "1991-11", "1991-12",
"1992-01", "1992-03", "1992-04", "1992-05", "1992-06", "1992-07",
"1992-08", "1992-09", "1992-10", "1992-11", "1992-12", "1993-01",
"1993-02", "1993-03", "1993-04", "1993-05", "1993-07", "1993-08",
"1993-09", "1993-10", "1993-12", "1994-02", "1994-03", "1994-04",
"1994-05", "1994-07", "1994-08", "1994-09", "1994-10", "1994-11",
"1994-12", "1995-04", "1995-05", "1995-06", "1995-07", "1995-08",
"1995-09", "1995-10", "1995-11", "1996-02", "1996-04", "1996-05",
"1996-06", "1996-07", "1996-08", "1996-09", "1996-11", "1996-12",
"1997-01", "1997-02", "1997-04", "1997-06", "1997-07", "1997-08",
"1997-09", "1997-10", "1998-01", "1998-02", "1998-04", "1998-05",
"1998-06", "1998-08", "1998-09", "1998-10", "1998-11", "1998-12",
"1999-03", "1999-05", "1999-06", "1999-07", "1999-08", "1999-09",
"1999-10", "1999-11", "1999-12", "2000-01", "2000-02", "2000-05",
"2000-06", "2000-07", "2000-08", "2000-09", "2000-10", "2000-11",
"2000-12", "2001-02", "2001-03", "2001-04", "2001-05", "2001-07",
"2001-08", "2001-09", "2001-10", "2001-11", "2001-12", "2002-01",
"2002-02", "2002-04", "2002-05", "2002-06", "2002-08", "2002-09",
"2002-10", "2002-11", "2002-12", "2003-01", "2003-02", "2003-03",
"2003-04", "2003-05", "2003-06", "2003-07", "2003-08", "2003-09",
"2003-12", "2004-01", "2004-02", "2004-03", "2004-04", "2004-05",
"2004-06", "2004-07", "2004-08", "2004-09", "2004-10", "2004-11",
"2004-12", "2005-01", "2005-02", "2005-03", "2005-04", "2005-06",
"2005-07", "2005-08", "2005-09", "2005-10", "2005-12"), class = "factor"),
    Freq = as.integer(c(3, 1, 1, 2, 3, 1, 1, 1, 1, 1, 2, 1, 2,
    1, 1, 1, 2, 1, 1, 1, 3, 2, 1, 1, 3, 1, 1, 2, 1, 2, 1, 2,
    1, 1, 2, 2, 3, 3, 2, 2, 1, 1, 1, 1, 1, 2, 2, 1, 2, 1, 2,
    1, 2, 1, 1, 1, 2, 2, 1, 1, 2, 1, 2, 1, 2, 2, 2, 2, 1, 2,
    1, 1, 2, 2, 1, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 3, 2, 2, 1,
    1, 1, 1, 1, 2, 3, 2, 4, 2, 2, 1, 3, 1, 3, 2, 1, 1, 2, 1,
    2, 1, 1, 2, 2, 2, 2, 3, 1, 1, 2, 1, 2, 1, 2, 2, 1, 1, 1,
    1, 2, 2, 1, 1, 2, 2, 2, 1, 1, 1, 1, 1, 1, 3, 1, 2, 1, 2,
    2, 1, 2, 1, 2, 3, 3, 1, 2, 1, 1, 2, 1, 1, 1, 1, 2, 2, 2,
    1, 2, 2, 1, 2))), .Names = c("Var1", "Freq"), row.names = 
as.integer(c(NA,
170)), class = "data.frame")