Standard deviation and plots

There's a good example of such an overlay at:

http://zoonek2.free.fr/UNIX/48_R/03.html

Look for a chart called "Third moment (skewness)".  The example shows 
how to calculate dimensions and draw a vertical line segment overlaid 
on the histogram.  Although he isn't doing exactly what you're looking 
for, the code could be easily modified for your use.   

There's a lot of other good stuff there, as well.

Enjoy,

pcc

Is there a way to display brackets 1sigma, 2sigma in combination with
actual values on the x scale in histogram plots or any other type of
plots? I am not quite sure how this would be accomplished but if its
possible to squeeze in the sigma brackets it would be great.

Thank you

Peter Carl
145 Scottswood Rd
Riverside, IL 60546
708.447.6465