[R] z-transform each column of a data.frame

[Peter Langfelder]

On Fri, Jan 20, 2012 at 9:04 AM, Martin Batholdy
<batholdy at googlemail.com> wrote:
> Hi,
>
>
> I am currently trying to z-transform (that is subtracting the mean and divide by the standard deviation) multiple columns of a data.frame at the same time.
>
>
> My first approach was:
>
> x <- data.frame(c(0:10), c(10:20))
> (x - colMeans(x)) / apply(x, 2, sd)
>
>
> This is obviously not working.
>
> Is there a convenient way to z-transform each column separately (so in this case, each column represents an independent variable that should be z-transformed)

scale(x) will scale each column of a matrix/ data frame to mean 0 and
variance 1.

Peter