I tried to get Apple's Numbers app to solve circular references, but all I got was a warning: "This formula can't reference its own cell or depend on another formula that references this cell." Normally, this is good advice, but there are some problems that can't be solved without a circular reference. MS Excel is very good at this and does it through iteration until a solution is reached. Excel's Preferences allow the user to set the Maximum Iterations and the Maximum Change between iterations in order to arrive at a solution. Sometimes, a solution cannot be reached within the specified number of iterations, but most of the time, the problem is solved. In my work, this feature is exceedingly valuable.
Wow, that's interesting. It would never occur to me to actually use a circular reference intentionally in a spreadsheet.
I do not believe there is any way to do what you're describing in Numbers. I'm frankly a bit surprised that Excel can do it. That must have been something of a programming nightmare, I reckon.
