[R] Length of data.frame column

[Petr PIKAL]

Hi

> 
> I have a related question...I have a data frame similar with 74 rows 
that I
> created with "header=TRUE", but when I try to coerce one of the data 
frame
> columns into a vector, it shows up as having length 1, even though when 
I
> print it, it shows 74 elements:
> 
> > VAL <- c(DailyDiary[1])
> > VAL
> > [1] 3 3 3 2 3 3 4 4 3 3 2 1 1 4 3 3 2 3 3 2 2 3 3 3 1 2 2
> [28] 1 1 3 3 3 2 4 3 2 3 4 3 3 3 3 4 3 2 3 2 3 1 2 1 2 3 1
> [55] 0 3 2 4 3 1 2 3 1 1 1 4 3 2 1 2 3 3 3 2
> >length(VAL)
> [1] 1

your VAL is still data frame. See ?"[" and link to data.frame method. Use 

str(object) 

to see the structure of your object not just printing it to console as 
print is a function which has also different methods for different objects 
and does not inform you about nature of your object.

You shall profit from reading R-intro which I believe you have overlooked. 
It shall be installed in doc/manual directory of your R installation.

Regards
Petr

> 
> On the other hand, I can easily coerce the row names to a vector of 
length
> 74
> 
> > partf <- row.names(DailyDiary)
> > length(partf)
> [1] 74
> 
> What I would like to do is make VAL into a vector with length 74 instead 
of
> length 1 so I can sort it using use "partf" as factors.  I tried
> "as.vector", but it doesn't let you specify the length.  Any ideas? 
Thanks,
> and sorry if I'm being unclear or stupid, I'm a newbie :)
> 
> Logan
> 
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