Thanks for all the info! Much appreciated.
I used to own a RO1 case (I think that was the name) that protected the Psion Org 2 from dirt and water. When my brother was doing his A Level project looking at the correlation between fish length and body mass of fish he caught on the beach in nets, I wrote him a program in OPL to log his catches.
He'd walk out to his nets at low tide, with Organiser LZ in hand (or actually on a lanyard around his neck!) in its RO1 case, and measure the length of each fish in the net. The application let you select the type of fish (Dover sole, plaice, dab etc..) then enter its length and mass (he took a small set of fishing scales with him if I recall correctly.) I also seem to remember spending ages making UDG for each fish species to make the app even more "professional" - or so I thought aged 17!
At the end of each session, the code would run through each fish species, calculate the length to mass ratio and add the data to a data file. At the end of the data collection period (6 weeks of the summer holiday) another bit of code calculated the regression between body length and mass, such that you could then predict the mass of a fish from its length alone. The correlation was pretty accurate from memory (0.95 or similar).
Anyway, the Psion did a great job of logging the data and producing a simple "model" to help save time weighing the fish. A quick measure of its length gave you a pretty good estimate of its weight.
Happy days! - I loved tinkering with my Psion, but loved it even more when I could code something up (not elegant, but did the job) so that my Psion could be used to actually do useful stuff
Anyway, got a bit carried away there. Might be of interest to someone though!
All the best,
Paul.