[R] problems in read.table

[Peter Dalgaard]

tkobayas at indiana.edu wrote:
> Dear R-users,
>
> I have encountered the following problem every now and then. But I was 
> dealing with a very small dataset before, so it wasn't a problem (I 
> just edited the dataset in Openoffice speadsheet). This time I have to 
> deal with many large datasets containing commuting flow data. I 
> appreciate if anyone could give me a hint or clue to get out of this 
> problem.
>
> I have a .dat file called "1081.dat": 1001 means Birmingham, AL.
>
> I imported this .dat file using read.table like
> tmp<-read.table('CTPP3_ANSI/MPO3441_ctpp3_sumlv944.dat',header=T)
>
> Then I got this error message:
> Error in scan(file, what, nmax, sep, dec, quote, skip, nlines, na.strings,  :
>         line 9499 did not have 209 elements
>
> Since I got an error message saying other rows did not have 209 
> elements, I added skip=c(205,9499,9294)) in hoping that R would take 
> care of this problem. But I got a similar error message:
> tmp<-read.table('CTPP3_ANSI/MPO3441_ctpp3_sumlv944.dat',header=T,skip=c(205,9499,9294))
> Error in scan(file, what, nmax, sep, dec, quote, skip, nlines, na.strings,  :
>         line 9294 did not have 209 elements
> In addition: Warning message:
> the condition has length > 1 and only the first element will be used 
> in: if (skip > 0) readLines(file, skip)
>
> Is there any way to let a R code to automatically skip problematic 
> rows? Thank you very much!
>
>   
Skip is the NUMBER of rows to skip before reading. It has to be a single 
number.

You can use fill and flush to read lines with too few or too many 
elements, but it might be better to investigate the cause of the 
problem. What are in those lines? Quote and comment characters are 
common culprits.

> Taka
>
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>   


-- 
   O__  ---- Peter Dalgaard             Øster Farimagsgade 5, Entr.B
  c/ /'_ --- Dept. of Biostatistics     PO Box 2099, 1014 Cph. K
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