[R] Plot Data Points in boxplots

[Jim Lemon]

Aric Gregson wrote:
> Hello,
> 
> I would like to plot my data in a fashion similar to a boxplot, but 
> plot the true data points without a box, just overlay lines of the 
> summary generated by the boxplot. I have less than 10 observations 
> within each group, so I think showing the actual data would be more 
> effective than the box of the boxplot. I have been unable to find a way 
> to do this.
> 
> Here is example data:
> 
>>d168teni
> 
>   d168dh10i d168hb10i d168icc10i d168rcs10i d168t410i d168tb410i
> 1        72        52         29         80        39         68
> 2        76        47         28         68        49         21
> 3       123        85         87         71       164        137
> 4        58        47         50         70        18          1
> 
> 
>>boxplot(d168teni)
> 
> 
> works to describe the data (each column a column in the plot). However, 
> instead of the boxes, I want the data plotted (in a column) with the 5 
> summary lines drawn over the points.
> 
> I have tried using functions from Design and have been unable to find a 
> solution. I think I am missing the point.
> 
> Any suggestions on where to look or how to approach this differently?
> 
I haven't seen anything like this posted, so I'll take a punt.

noboxplot<-function(x,plot=FALSE,...) {
  boxplot.info<-boxplot(x,plot,...)
  dimx<-dim(x)
  if(is.null(dimx)) plot(1,x)
  else {
   xpts<-1:dimx[2]
   # you may want to use text() here if you want the
   # actual values displayed
   matplot(t(as.matrix(x)),axes=FALSE,xlim=c(0.5,dimx[2]+0.5),
    ylab=deparse(substitute(x)))
  }
  box()
  axis(2)
  nbp.labels<-names(x)
  if(is.null(nbp.labels)) nbp.labels<-as.character(xpts)
  axis(1,at=xpts,labels=nbp.labels)
  for(xpos in 1:dimx[2]) {
   segments(xpos-0.2,boxplot.info$stats[,xpos],
            xpos+0.2,boxplot.info$stats[,xpos],
	   lwd=c(1,1,3,1,1))
  }
  return(boxplot.info)
}

Hope it's what you want.

Jim