[R] Change class factor to numeric

[Gavin Simpson]

Smit, R. (Robin) (IenT) wrote:
> I am attempting to develop a multiple regression model using selected
> model variables that should all be treated as numeric (mostly real)
> values.
> However, R considers one specific variable "mass" automatically to be of
> class "factor", probably because "mass" consists of integer values that
> are repeated.
> I now want to force R to treat "mass" as a numeric variable in the
> regression but am not sure how to do this.
>  
> 
>>class(mass) <- "numeric"
> 
>  
> does not help me.
>  
> Could anyone advise me on this?

It is in the FAQ

7.10 How do I convert factors to numeric?

http://cran.r-project.org/doc/FAQ/R-FAQ.html#How-do-I-convert-factors-to-numeric_003f

HTH

Gav
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Gavin Simpson                     [T] +44 (0)20 7679 5522
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