[R] Separate x-axis ticks for panels in xyplot()?

[Michael Kubovy]

Dear r-helpers,

In an xyplot I have

xyplot(y ~ x | c, groups = g,
	scales = list(
		x = list(
			at = v1,
			labels = c('A', 'B', 'C', 'D'),
			rot = 45
		)
	)
)

g consists of two groups. How do I define a different set of x ticks  
and labels for the second panel? I'm looking for something like

xyplot(y ~ x | c, groups = g,
	scales = list(
		x = list(ifelse(g == g1, {
			at = v1,
			labels = c('A', 'B', 'C', 'D'),
			rot = 45},
			{at = v2,
			labels = c('E', 'F' 'G"),
			rot = 45}
		)
	)
)


_____________________________
Professor Michael Kubovy
University of Virginia
Department of Psychology
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