[R] Scaling values 0-255 -> -1 , 1 - how can this be done?

[Rainer Schuermann]

x <- as.data.frame( matrix( 0:255, nrow = 16 ) )
ifelse( x > 127.5, 1, -1 )

Is that what you want?

Rgds,
Rainer


On Wednesday 21 November 2012 10:32:49 Brian Feeny wrote:
> 
> I have a dataframe in which I have values 0-255, I wish to transpose them such that:
> 
> if value  > 127.5 value = 1
> if value < 127.5 value = -1
> 
> I did something similar using the "binarize" function of the biclust package, this transforms my dataframe to 0 and 1 values, but I wish
> to use -1 and 1 and looking for a way in R to do this.
> 
> Brian
> 
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