I have found this a useful thread on the Steorn forum so I am starting one here. Perhaps there is not quite the same need for it since the preview facility is very good - but there is aways a danger of pressing the wrong button an posting something one didn't want to so I feel happier in trying different bits of code in a dedicated thread like this one.
(https://overunityarchives.com/proxy.php?request=http%3A%2F%2Fi136.photobucket.com%2Falbums%2Fq171%2Ffrank260332%2FBindingenergycurve.gif&hash=6312dd248b976e67af894477f50b83d4fe32ba84)