[R] r bug (?) display of data

[Peter Dalgaard]

Marc Jekel wrote:
> Hi R Fans,
> 
> I stumbled across a strange (I think) bug in R 2.9.1. I have read in a 
> data file with 5934 rows and 9 columns with the commands:
> 
> daten = data.frame(read.table("C:/fussball.dat",header=TRUE))
> 
> Then I needed a subset of the data file:
> 
> newd = daten[daten[,1]!=daten[,2],]
> 
> --> two values do not meet the logical specification and are dropped.
> 
> The strange thing about it: When I print the newd in the R Console, the 
> output still shows 5934 rows. When I check the number of rows with 
> NROW(newd) , I get 5932 as output. When I print newd[5934, ], I get NAs. 
> When I print newd[5932, ] I get the row that is listed in line 5934 when 
> I just type in newd. This is totally crazy! Has anyone had the same 
> problem? Thanks for a post.

You're confusing row names and row numbers. When you printed newd, did 
you actually count the number of lines? Thought so...

It isn't any stranger than this:

 > data.frame(x=rnorm(6),y=rnorm(6))[-5,]
            x          y
1  0.9457385 -1.1398275
2 -1.1683732 -0.7269941
3  0.9942821  0.9310146
4 -2.0839580 -0.6261567
6  1.7225233  0.2457897


-- 
    O__  ---- Peter Dalgaard             Øster Farimagsgade 5, Entr.B
   c/ /'_ --- Dept. of Biostatistics     PO Box 2099, 1014 Cph. K
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~~~~~~~~~~ - (p.dalgaard at biostat.ku.dk)              FAX: (+45) 35327907