[R] Combine 'overlapping' dataframes, respecting row names

[James Howison]

Hi,

I've examined the archives and found quite a few questions on  
concatenating dataframes, but none that really addressed my issue,  
I'm afraid.  I've also examined the cbind and rbind documentation but  
nonetheless here I am writing to r-help ;)

This is what I have (the row names are dates used for conversion to  
an irregular time series with the its package):

 > cvsFrame
            cvsactions
2002-11-15          4
2002-12-15          9
2003-01-15          5
2003-02-15          5

 > downloadsFrame
             downloads
2002-09-15          1
2002-10-15          2
2002-11-15         12
2002-12-15          8

(notice how the dates are overlapping?)

The output I'd like is:

            cvsaction  downloads
2002-09-15       NA          1
2002-10-15       NA          2
2002-11-15       4          12
2002-12-15       9           8
2003-01-15       5          NA
2003-02-15       5          NA

ie. merge the data.frames, respecting the row.names and inserting NAs  
where a frame didn't contain info for a row in the final frame.

This is the closest I gotten (I'm sure cbind is doing what it's meant  
to do but it's obviously not what I need)

 > cbind(downloadsFrame,cvsFrame)
             downloads cvsactions
2002-09-15          1          4
2002-10-15          2          9
2002-11-15         12          5
2002-12-15          8          5

It takes the row.names from the first frame given and then just adds  
the data in rows 1 through 4, regardless of their row.name. And it  
doesn't work at all if the column lengths are different. (Yes, it  
would be nice if the 'its' class had a way to merge 'its' objects,  
but the question seemed general enough to ask on list.)

Thanks,
James