[R] Append to csv without header

[David Winsemius]

On Aug 11, 2010, at 10:29 PM, harsh yadav wrote:

> Hi,
>
> I am writing a function that writes to a csv file for every call.
>
> However, for the subsequent calls, I want to append the data to the  
> existing
> csv file without appending the column names again.
>
> I tried searching in the previous posts, but I am stuck with different
> errors.
>
> Here is what I am doing (dataF is a data-frame):-
>
> outputFilePath <- paste(getwd(), "/", "outputModel.csv", sep="");
>
> counter <- 1
> for (userid in userids){
>       dataF <- getUserData(userid)
>
>        if(counter == 1){
> write.csv(dataF, file = outputFilePath, append=F)
> }else{
> write.csv(dataF, file = outputFilePath, append=T,col.names=NA)
> }
>
>       counter <- counter + 1
> }
>
> I tried setting col.names = F (In append=T), but no good.
>
> Can anyone throw light on the correct usage.

Change second write.csv to write.table, add a sep argument.

write.csv() ignores an append argument. The second line of its code is:

for (argname in c("append", "col.names", "sep", "dec", "qmethod")) if  
(!is.null(Call[[argname]]))
         warning(gettextf("attempt to set '%s' ignored", argname),
             domain = NA)

Didn't you believe the warnings?

-- 
David.
>
> Thanks in advance.
>
> Regards,
> Harsh Yadav
>
> 	[[alternative HTML version deleted]]
>
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David Winsemius, MD
West Hartford, CT