[R] from character to numeric over multiple columns

[Federico Calboli]

Prof Brian Ripley wrote:
> Are the columns factors or character?  I'll try to write code that copes 
> with both:
> 
> nm <- unique(c(as.character(col1), as.character(col2), as.character(col3)))
> 
> DF[] <- lapply(DF, function(x) match(x, nm))

Cheers,

it worked.

Federico

-- 
Federico C. F. Calboli
Department of Epidemiology and Public Health
Imperial College, St Mary's Campus
Norfolk Place, London W2 1PG

Tel  +44 (0)20 7594 1602     Fax (+44) 020 7594 3193

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