R help - Oct 2005 - biplot.default

Hi,

I've been trying to understand biplot. From
getAnywhere(biplot.default), I could get the source code. However, there
is one line that did make sense to me. It's the second line from the
bottom.

arrow(0, 0, y[,1]*0.8, y[,2]*0.8, col = col[2],....)

I don't understand why there is a multiplication by 0.8 for y.

Thanks.

On Tue, 18 Oct 2005, Jungyeon Yoon wrote:
> I've been trying to understand biplot. From
> getAnywhere(biplot.default), I could get the source code. However, there
> is one line that did make sense to me. It's the second line from the
> bottom.
>
> arrow(0, 0, y[,1]*0.8, y[,2]*0.8, col = col[2],....)
>
> I don't understand why there is a multiplication by 0.8 for y.
Try it without to see. It is to help the aesthetics of the plot.

-- 
Brian D. Ripley,                  ripley at stats.ox.ac.uk
Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
University of Oxford,             Tel:  +44 1865 272861 (self)
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