[R] meaning of lm( y~., data=mydat ), is it a language feature, is it documented, is it supported?

[Kenneth Knoblauch]

John Sorkin <JSorkin <at> grecc.umaryland.edu> writes:
> The syntax
> mydat <- data.frame( y,x )
> fit1 <- lm( y~., data=mydat )
> appears to perform a multivariable regression of y on 
every non-y variable in the data frame mydat. I can not
> find this syntax (y~.) in R documentation. Is y~. 
a supported feature of the R language? Where can I find it
> documented? I would hate to write code that
 is dependent on a non-supported, non-documented 
language feature.
> Thank you,
> John
> John David Sorkin M.D., Ph.D.
> Professor of Medicine
> Chief, Biostatistics and Informatics
> University of Maryland School of 
Medicine Division of Gerontology and Geriatric Medicine
> Baltimore VA Medical Center
> 10 North Greene Street
> GRECC (BT/18/GR)
> Baltimore, MD 21201-1524
> (Phone) 410-605-7119
> (Fax) 410-605-7913
> 

How about section 11.5 of An Introduction to R?

-- 
Kenneth Knoblauch
Inserm U1208
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