R help - May 2010 - writing autocorrelation and partial auto correlation functions to a file

Dear All,
          I am very new to T.  I need to fit a ARIMA model to my time
series.  So I found the auto correlation functions and partial auto
correlation function in R. Now I want to save these valuse along with the
significance levels to a file.  How to do that?.  I tried some function in R
like write.table but returns an error  "cannot coerce class "acf"
into a
data.frame".  The I tried "write"
but returned again an error "Error in cat(list(...), file, sep, fill,
labels, append) :
  argument 1 (type 'list') cannot be handled by 'cat'".
Where am I going wrong

THanks in advance
nuncio
-- 
Nuncio.M
Research Scientist
National Center for Antarctic and Ocean research
Head land Sada
Vasco da Gamma
Goa-403804

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The problem is that the acf function (like many R functions) returns a list
containing many different things. For example, I have a short series in
the vector z:
> acz <- acf(z)
> str(acz)
List of 6
 $ acf   : num [1:11, 1, 1] 1 -0.0668 -0.7401 0.0627 0.5954 ...
 $ type  : chr "correlation"
 $ n.used: int 11
 $ lag   : num [1:11, 1, 1] 0 1 2 3 4 5 6 7 8 9 ...
 $ series: chr "z"
 $ snames: NULL
 - attr(*, "class")= chr "acf"

Let's say you are interested in extracting the acf and lag values from that
> acd <- data.frame(cbind(lag=acz$lag,acf=acz$acf))
> acd
   lag         acf
1    0  1.00000000
2    1 -0.06676557
3    2 -0.74006273
4    3  0.06266564
5    4  0.59542482
6    5 -0.06786556
7    6 -0.41370293
8    7  0.03464621
9    8  0.21887326
10   9 -0.07485743
11  10 -0.04835570

On May 20, 2010, at 3:38 AM, nuncio m wrote:
> Dear All,
>          I am very new to T.  I need to fit a ARIMA model to my time
> series.  So I found the auto correlation functions and partial auto
> correlation function in R. Now I want to save these valuse along  
> with the
> significance levels to a file.  How to do that?.  I tried some  
> function in R
> like write.table but returns an error  "cannot coerce class
"acf"
> into a
> data.frame".  The I tried "write"
> but returned again an error "Error in cat(list(...), file, sep, fill,
> labels, append) :
>  argument 1 (type 'list') cannot be handled by 'cat'".
> Where am I going wrong
If you are just interested in getting the same information that you  
see on the console into a text file then:

?capture.output

-- 

David Winsemius, MD
West Hartford, CT