On 3/31/06, Sundar Dorai-Raj <sundar.dorai-raj at pdf.com> wrote:
>
>
> Andy Bunn wrote:
> > Is there is a way to make square bars in xyplot with type="h"?
> >
> > dat <- data.frame(foo = rep(1:10,2), bar = rep(1:10,2))
> > xyplot(foo~bar, data = dat, type="h",lwd=20)
> >
> > Thanks! Andy
> >
>
>
> Hi, Andy,
>
> I don't think lattice supports this since it uses
> trellis.par.get("plot.line") to determine the drawing parameters.
> However, you can use the grid package.
>
> library(lattice)
> library(grid)
> dat <- data.frame(foo = rep(1:10,2), bar = rep(1:10,2))
> xyplot(foo ~ bar, data = dat,
> panel = function(x, y, ...) {
> ## hacked from lattice::lplot.xy
> ylim <- current.viewport()$yscale
> zero <- if (ylim[1] > 0)
> ylim[1]
> else if (ylim[2] < 0)
> ylim[2]
> else 0
> gp <- gpar(lty = 1, col = "blue", lwd = 20,
> alpha = 1, lineend = "square")
> grid.segments(x0 = x, x1 = x, y0 = y, y1 = zero,
> gp = gp, default.units = "native")
> })
Right. R 2.3.0 should have better support for grid parameters (that
are not anticipated by lattice), where both of the following should
work:
xyplot(foo~bar, data = dat, type="h",lwd=20,
par.settings = list(grid.pars = list(lineend = 1)))
xyplot(foo~bar, data = dat, type="h",lwd=20, lineend = 1)
The first solution should already work in the current alpha of R
2.3.0, I'm testing the second one now.
Deepayan