R help - Jan 2010 - Boxplot- input the median point and the median value

Dear,

I am a newbie to R.

Now I am learning to draw boxplot using graphics().

I want to highlight the median position

with a round point and the value left (or on the top of)to the point.



Please kindly share the command and thank you.

Elaine

	[[alternative HTML version deleted]]

Dear Elaine,

The posting guide is
http://www.R-project.org/posting-guide.html<http://www.r-project.org/posting-guide.html>

bests

milton

On Fri, Jan 1, 2010 at 8:53 PM, elaine kuo <elaine.kuo.tw@gmail.com>
wrote:
>  Dear,
>
> I am a newbie to R.
>
> Now I am learning to draw boxplot using graphics().
>
> I want to highlight the median position
>
> with a round point and the value left (or on the top of)to the point.
>
>
>
> Please kindly share the command and thank you.
>
> Elaine
>
>        [[alternative HTML version deleted]]
>
> ______________________________________________
> R-help@r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide
>
http://www.R-project.org/posting-guide.html<http://www.r-project.org/posting-guide.html>
> and provide commented, minimal, self-contained, reproducible code.
>
	[[alternative HTML version deleted]]

On 01/02/2010 12:53 PM, elaine kuo wrote:
>   Dear,
>
> I am a newbie to R.
>
> Now I am learning to draw boxplot using graphics().
>
> I want to highlight the median position
>
> with a round point and the value left (or on the top of)to the point.
>
>
>    
Hi Elaine,

For your boxplot questions, I'll use the first example from the boxplot 
help page:

boxplot(count ~ spray, data = InsectSprays,
  col = "lightgray",yaxt="n")
axis(2,c(2,8,14,20),c(2,8,14,20))

For the "dotted to solid" question:

boxplot_info<-boxplot(count ~ spray,
  data = InsectSprays,col = "lightgray")
segments(rep(1:6,each=2),boxplot_info$stats[c(1,4),],
  rep(1:6,each=2),boxplot_info$stats[c(2,5),])

And finally, for the median value question:

boxplot_info<-boxplot(count ~ spray, data = InsectSprays,
  col = "lightgray")
points(1:6,boxplot_info$stats[3,])
text(1:6,boxplot_info$stats[3,]+1,boxplot_info$stats[3,])

A bit messy, but you get the idea.

Jim