[R] several regression lines in panel of xyplot (trellis graphics)

[Wladimir Eremeev]

Dear r-help,

  I need to draw xyplot() graphs with several regression lines:
  one line for the whole range of x (the variable on the horizontal
  axis) and two additional lines for subranges of x.
  
  Is it possible to make first regression line (panel.lmline(x,y,...);)
  to be drawn on the whole graph
  and regression lines of the subsets to be drawn only over their subsets?

  I have defined
plot.panel=function(x,y,...){
  panel.xyplot(x,y,...);
  panel.lmline(x,y,...);
  panel.lmline(x[1:9],y[1:9],...);
  panel.lmline(x[10:23],y[10:23],...);
  panel.grid(h=-1,v=-1,...);
};

then I draw plots:
  xyplot(<blah-blah-blah>,panel=plot.panel,<...>)

  This command draws graphics, but all regression lines on them are
  drawn from the left side to the right side, i.e. over the whole x
  range...

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

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