R help - Apr 2008 - Making a data frame into a factor ?

Hi,
   I'm trying to do a linear regression style one-way ANOVA using some
data in a data frame, and (perhaps because I am still relatively
unfamiliar with both R and statistics) what I thought I should do was
to make the data frame into a factor.  By that I mean that I have a
data frame whose column labels are the levels of the factor, and the
values in the frame are numeric values for the dependent variable.
   I can construct the relevant vectors by hand, if I have to (and I
guess I will start in that direction) but I am sure there must be 1-3
line bit of R that could elegantly create the factor and the vector of
values.
   Thanks in advance,

-- 
Paul Lynch
Aquilent, Inc.
National Library of Medicine (Contractor)

I think you want to look into ?stack. For example:

x<-data.frame(a=1:5,b=6:10)
y<- stack(x)

Then x$values are the values, and x$ind is the factor.

On Apr 15, 2008, at 9:36 PM, Paul Lynch wrote:
> Hi,
>    I'm trying to do a linear regression style one-way ANOVA using some
> data in a data frame, and (perhaps because I am still relatively
> unfamiliar with both R and statistics) what I thought I should do was
> to make the data frame into a factor.  By that I mean that I have a
> data frame whose column labels are the levels of the factor, and the
> values in the frame are numeric values for the dependent variable.
>    I can construct the relevant vectors by hand, if I have to (and I
> guess I will start in that direction) but I am sure there must be 1-3
> line bit of R that could elegantly create the factor and the vector of
> values.
>    Thanks in advance,
>
> -- 
> Paul Lynch
> Aquilent, Inc.
> National Library of Medicine (Contractor)
Haris Skiadas
Department of Mathematics and Computer Science
Hanover College