[R] watermarks

[kjetil@acelerate.com]

On 14 May 2004 at 11:45, Karla Meurk wrote:

> Hi, I would like to plot a graph which sits in the background as a
> watermark with other plots in the foreground - on top.  I have looked
> through the threads on the r-project website but they seem to concern
> background colours rather than actual background plots.  I have also
> searched through the demo's and pars but can't find any eg's
> 
> any ideas - I only want to plot a simple graph using pie.chart()
> 

You can do this with the pixmap package. 
library(pixmap) and so
?pixmap
An example based on ?pixmap:

> ## Another example that math can be beautiful
>  x <- seq(-3,3,length=100)
>  z1 <- outer(x,x,function(x,y) abs(sin(x)*sin(y)))
>  z2 <- outer(x,x,function(x,y) abs(sin(2*x)*sin(y)))
>  z3 <- outer(x,x,function(x,y) abs(sin(x)*sin(2*y)))
> 
>  ## Notice that we specify a bounding box to get the correct
>  ## coordinates on the axes. z1, z2 and z3 are used as red,
>  ## green and blue channel, respectively.
>  z <- pixmapRGB(c(z1,z2,z3), 100, 100, bbox=c(-1,-1,1,1))
>  plot(z, axes=TRUE)
> par(new=TRUE)
> plot( (-20:20)/20, (-20:20)/20, xaxt="n", yaxt="n", ann=FALSE)
> 


Kjetil Halvorsen

> Thanks
> 
> Carla
> 
> ______________________________________________
> R-help at stat.math.ethz.ch mailing list
> https://www.stat.math.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide!
> http://www.R-project.org/posting-guide.html
>