Hi,
I am trying to append tables on file with this sample code:
for(i in 1:2){
mat <- data.frame(sample(1:30,9),3,3)
colnames(mat) <- letters[1:3]
ifelse(i
=1,write.table(mat,paste('test.txt',sep=''),row.names=F),
write.table(mat,paste('test.txt',sep=''),row.names=F,col.names=F,append=TRUE))
}
However, this gives an error:
"Error in ifelse(i == 1, write.table(mat, paste("test.txt", sep =
""), :
replacement has length zero"
- Should I be passing in some other parameters or using a different
function to append tables to file?
thanks!
[[alternative HTML version deleted]]
I believe your problem stems from using ifelse() actually ... it
requires the statements which it runs to return a value with the same
shape as the test, which write.table() isn't doing.
Just change it to a regular if with an else and you'll be fine:
for(i in 1:2){
mat <- data.frame(sample(1:30,9),3,3)
colnames(mat) <- letters[1:3]
if(i == 1){
write.table(mat,paste('test.txt',sep=''),row.names=F)
} else {
write.table(mat,paste('test.txt',sep=''),row.names=F,col.names=F,append=TRUE)
}
}
Hope that helps,
Louis
On Fri, Feb 8, 2013 at 2:40 PM, Brian Smith <bsmith030465 at gmail.com>
wrote:>
> Hi,
>
> I am trying to append tables on file with this sample code:
>
> for(i in 1:2){
> mat <- data.frame(sample(1:30,9),3,3)
> colnames(mat) <- letters[1:3]
> ifelse(i =>
1,write.table(mat,paste('test.txt',sep=''),row.names=F),
>
>
write.table(mat,paste('test.txt',sep=''),row.names=F,col.names=F,append=TRUE))
> }
>
> However, this gives an error:
>
> "Error in ifelse(i == 1, write.table(mat, paste("test.txt",
sep = ""), :
> replacement has length zero"
>
> - Should I be passing in some other parameters or using a different
> function to append tables to file?
>
> thanks!
>
> [[alternative HTML version deleted]]
>
> ______________________________________________
> R-help at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide
http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
Hi, On Feb 8, 2013, at 9:40 AM, Brian Smith wrote:> Hi, > > I am trying to append tables on file with this sample code: > > for(i in 1:2){ > mat <- data.frame(sample(1:30,9),3,3) > colnames(mat) <- letters[1:3] > ifelse(i => 1,write.table(mat,paste('test.txt',sep=''),row.names=F), > > write.table(mat,paste('test.txt',sep=''),row.names=F,col.names=F,append=TRUE)) > } > > However, this gives an error: > > "Error in ifelse(i == 1, write.table(mat, paste("test.txt", sep = ""), : > replacement has length zero" > > - Should I be passing in some other parameters or using a different > function to append tables to file?You might try assign each parameter based upon the value of i instead of trying to manage two different calls to write.table through an ifelse function. ifelse doesn't seem to like the value returned by write.table (NULL). Here's a simply example...> ok <- ifelse( TRUE, NULL, NULL)Error in ifelse(TRUE, NULL, NULL) : replacement has length zero> ok <- ifelse( FALSE, NULL, NULL)Error in ifelse(FALSE, NULL, NULL) : replacement has length zero I think that is what the warning in ?ifelse is alluding to. You would only know that write.table returns NULL if you have bitten by it before. I have bite marks. for(i in 1:2){ mat <- data.frame(sample(1:30,9),3,3) colnames(mat) <- letters[1:3] write.table(mat, file = "test.txt", row.names = FALSE, col.names = (i == 1), append = (i != 1) ) } Cheers, Ben> > thanks! > > [[alternative HTML version deleted]] > > ______________________________________________ > R-help at r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code.Ben Tupper Bigelow Laboratory for Ocean Sciences 60 Bigelow Drive, P.O. Box 380 East Boothbay, Maine 04544 http://www.bigelow.org