[R] read.table() with "\t" as seperator, all other programs report equal fields each row, read.table() returns unequal row length error

[peter dalgaard]

On Mar 16, 2011, at 17:37 , Yong Wang wrote:

> hi, list
> 
> R is undoudtedly my favorite statistic tool, however, the data
> inputnpart has long been a pain. most data I have to deal with are
> irregular and contains special character.
> 
> Recently I get a tab delimited data, read.table(filename,sep="\t")
> constantly return erors for certain rows does not has xyz elements
> while all other programs such as perl,python, awk all report equal row
> length if use "\t" as seperator.
> 
> I scout through the problematic row, sometimes it is because a row
> contains a "#", so I go back to specify comment.char=""
> next it will be some other problems, for some rows I simply can't
> figure out what the problem is.
> 
> can I have any guru suggestion to save this pain now and in the
> future, is CSV a safer format? or can anyone let me know what are the
> fundamental principles I must bear in mind when do preliminary data
> processing using other programs such as perl to ensure the output can
> be readily feed into R.

A couple of other things can get messed up, e.g. quote symbols. Does read.delim()/read.delim2() perhaps work better?  

With CSV, you generally get the same sort of issues, just with "," instead of "\t". 


> 
> best
> 
> yong
> 
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-- 
Peter Dalgaard
Center for Statistics, Copenhagen Business School
Solbjerg Plads 3, 2000 Frederiksberg, Denmark
Phone: (+45)38153501
Email: pd.mes at cbs.dk  Priv: PDalgd at gmail.com