[R] barchart but with boxes

[Jim Lemon]

On 06/07/2010 04:53 PM, Daisy Englert Duursma wrote:
> Hello r-help.
>
> I have been working on making a graph and have several solutions but
> they are tedious at best.
>
> Here is an example dataset:
>
> catg<-(c(1,2,3,2,4,3,2,1,4,3,1))
> min<-(c(1,2,3,3,4,5,6,6,3,2,1))
> max<-(c(10,6,8,6,7,3,10,9,10,8,9))
> cbind(min,max,catg)
>
> What I want to create is a basically a bar chart,  but I define the
> min (min) and max (max) for the bars.
> These bars are separated into three categories (catg). Within each
> category the bars are allowed to overlap. I set the bars to have a
> transparent color so that I can see agreement of the  items within a
> category based on the darkness of color.
>
> One method I came up with, is to use ggplot2 and geom_tile but then I
> have to give x,y coordinates for every corner of every box.
> Considering the size of my real datasets, and not this little example
> dataset, this seems annoying.
>
> I could even just graph lines with the defined min and max. With that
> I could make the lines thick and achieve the effect I am looking for.
>
Hi Daisy,
How about this?

offset<-c(-0.1,-0.1,-0.1,0,-0.1,0,0.1,0,0,0.1,0.1)
plot(0,xlim=c(0.5,4.5),ylim=c(0,10),type="n")
segments(catg+offset,min,catg+offset,max,lwd=5,col=3)

You can program a function to calculate the offsets if you want to do 
lots of these.

Jim