On 3/5/08, Fredrik Karlsson <dargosch at gmail.com>
wrote:> Hi,
>
> In my discpipline, it is common to plot one acoustic property on a
> positive scale but from top to bottom on the ordinate and the same for
> another measurement on the abscissa.
> So, the origin of the plot is on the top right of the plot, with
> increasing values to the left /down. This is to highlight the
> correlation between the acoustic measurement and the position of the
> forming structure, for instance when teaching it to students.
>
> The grouping ability of the trellis plot is quite handy whan plotting
> many instances of the same thing, so I was wondering if it is possible
> to make a trellis xyplot behave this way?
> Converting all values to negative and changing labels to the negative
> of the negative seems one solution to the reverseness of the axes, but
> how do I change the position? Is it possible?
You can always specify explicit limits that are reversed, e.g.,
ylim=c(100, 0). If you want this as a general behaviour but don't know
your data's range beforehand, one option might have been
prepanel = function(x, y, ...) {
list(ylim = rev(range(y)))
}
Unfortunately, this doesn't work when relation="same", as the step
of
combining the per-panel limits to obtain a common range disregards the
order.
-Deepayan