R help - Nov 2006 - Combining factors

Hi

I know this is a basic question and I know I have done it before but I 
can't find the answer any more.

I have a data set, say:

F1, F2, Value

F1 and F2 are Factors.

I would like to plot

plot(TheCombinationOf(F1, F2), Value)

I remember there was a function for TheCombinationOf() but I don't 
remember the name.

I could create a new factor based on F1 and F2, but I would prefer the 
other soluytion.

Any help welcome,

Rainer


-- 
Rainer M. Krug, Dipl. Phys. (Germany), MSc Conservation
Biology (UCT)

Department of Conservation Ecology and Entomology
University of Stellenbosch
Matieland 7602
South Africa

Tel:		+27 - (0)72 808 2975 (w)
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email:	RKrug at sun.ac.za
       	Rainer at krugs.de

Rainer M Krug <RKrug at sun.ac.za> writes:
> Hi
> 
> I know this is a basic question and I know I have done it before but I 
> can't find the answer any more.
> 
> I have a data set, say:
> 
> F1, F2, Value
> 
> F1 and F2 are Factors.
> 
> I would like to plot
> 
> plot(TheCombinationOf(F1, F2), Value)
> 
> I remember there was a function for TheCombinationOf() but I don't 
> remember the name.
> 
> I could create a new factor based on F1 and F2, but I would prefer the 
> other soluytion.
> 
> Any help welcome,
F1:F2
interaction(F1,F2)

There are some differences so lookup the help page for the latter.

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