Lattice: how to get default ylim?

Hi,

Within your panel function you can use current.viewport() to recover
the active grid viewport and get xlim/ylim (in addition to other very
useful information).  Then you can use grid.text (plus any other
grid.* function), e.g.,

  require(grid)

  my.panel <-
  function(...)
  {
     panel.xyplot(...)

     ## add "Hello World on the top-left of each panel

     v <- current.viewport()        ## requires R 2.1.0 (I believe)

     xlim <- v$xscale
     ylim <- v$yscale
     grid.text(x = xlim[1], y = ylim[2], default.units="native",
        label = "Hello World", just= c("left", "top"))

  }

Hope this helps.

--
David

Wladimir Eremeev wrote:

Dear r-help,

  I draw graphics with xyplot and want to add some text to each panel
  (actually, the slope, error and significance of a regression line).

  I have defined the function, drawing a single panel and pass it to
  xyplot in the panel argument. This function calls panel.xyplot,
  calculates linear regression and formats coefficients.

  Now I want the text, I mentioned above, to be put in the upper left
  corner of each plot.
  I use ltext, and I need to define coordinates x and y.
  In order to do this I need to know the limits of x and y axes.

  I do not want to pass arguments xlim and ylim to the xyplot function
  and want it to calculate them automatically.
  And I also want to know the result of calculations. :)
  How to do this?

  Thank you very much.

--
Best regards
Wladimir Eremeev                                     mailto:wl at eimb.ru

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