>No one appears to have mentioned the problem of determining the correct >mathematical syntax. i.e number-operator-number-equals-number(and possibly >more operators & numbers) That is a good point, but I think that we've all designed parsers and lexical analyzers here, so it shouldn't be any more than a "go back to high school computer class" to resolve it. The parser/interpreter also handles the other points you made about multi-digit numbers, precedence, etc. >If you are going to model an equation, it would seem prudent to allow the >equal block to be the master in the system. You could then interogate Excellent idea! Andy ================================================================== Eternity is only a heartbeat away - are you ready? Ask me how! ------------------------------------------------------------------ andy@rc-hydros.com http://www.rc-hydros.com - Race Boats andy@montanadesign.com http://www.montanadesign.com - Electronics ==================================================================