Thanks Dave. This is what I need. I´m here because I want to learn. I don´t have a chance to apply it anywhere so far, and part of it goes above my head. However I´m learning a lot and I´m quite happy to be here. Reading, agreeing and disagreeing, feeling confused and amazed.My neural networks are at a loss, I´m sure; creating new connections. That´s good. I´ll be around, lurking? Sorry, George.