Great advice.  I did a quick read and came up with the following:
 
qplot(Age, data = recerts_combined_values, binwidth = 5, 
         fill = combined_values$Test.Type, 
         ylab="Counts", xlab="Age, months",  
         main="Combined Age Histogram", 
         legend.name = "Type of Tests")

Unfortunatley, here is a description of the results:
(1) the "main" title font size by default is too large and is clipped by the image (guess I need to figure out how to fix this), 
(2) ylab appears to fail - it does not replace the default "count" label - what should I do to fix this?
(3) like (2), neither using "legend.name" nor "legend.title" appears to replace/change the name of the legend title/name.  
 
By any chance can you provide some advice for tackeling these items?  These are probably due to me being a noobie on the ggplot2 package.  
 
Thanks again.
 

--- On Mon, 1/5/09, hadley wickham <h.wickham@gmail.com> wrote:

From: hadley wickham <h.wickham@gmail.com>
Subject: Re: [R] R Stacked Histogram
To: jasonkrupert@yahoo.com
Cc: r-help@r-project.org
Date: Monday, January 5, 2009, 7:42 AM

On Sun, Jan 4, 2009 at 6:51 PM, Jason Rupert <jasonkrupert@yahoo.com>
wrote:
> Understood.  Will head the warning about odd way to display data.
>
> Any recommendations about where I look to find full details about
"qplot".
>
> I tried ?qplot, but it did not return full details.
>
> That description was missing a few items, e.g. fill, which is used below.

The best place to start is the qplot chapter of the ggplot2 book -
http://had.co.nz/ggplot2/book

Regards,

Hadley

-- 
http://had.co.nz/



      
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