merging several dataframes from a list

Try this also:

 cbind(pos = mylist$df1$pos, data.frame(mylist)[grep("data", 
names(data.frame(mylist)))])

On Wed, Jan 21, 2009 at 6:19 AM, Antje <niederlein-rstat at yahoo.de 
<mailto:niederlein-rstat at yahoo.de>> wrote:

    Hi there,

    I have a list of dataframes (generated by reading multiple files)
    and all dataframes are comparable in dimension and column names.
    They also have a common column, which, I'd like to use for merging.
    To give a simple example of what I have:

    df1 <- data.frame(c(LETTERS[1:5]), c(2,6,3,1,9))
    names(df1) <- c("pos", "data")
    df3 <- df2 <- df1
    df2$data <- c(6,2,9,7,5)
    df3$data <- c(9,3,6,2,1)
    mylist <- list(df1,df2,df3)
    names(mylist) <- c("df1","df2","df3")

     > mylist

    $df1
     pos data
    1   A    2
    2   B    6
    3   C    3
    4   D    1
    5   E    9

    $df2
     pos data
    1   A    6
    2   B    2
    3   C    9
    4   D    7
    5   E    5

    $df3
     pos data
    1   A    9
    2   B    3
    3   C    6
    4   D    2
    5   E    1

    If I use do.call("cbind"), I'll end up with something like this

      pos data pos data pos data
    1   A    2   A    6   A    9
    2   B    6   B    2   B    3
    3   C    3   C    9   C    6
    4   D    1   D    7   D    2
    5   E    9   E    5   E    1


    but now, I don't know anymore which data comes from which
    dataframe... and I have the column "pos" multiple times...

    Instead I'd like to have it like this:

      pos df1 df2 df3
    1   A    2   6   9
    2   B    6   2   3
    3   C    3   9   6
    4   D    1   7   2
    5   E    9   5   1

    How, can I realize it? (The list, I'm working with has not just 3
    data frames like given in my example, so I need to automize it)


    Antje