# The 30+ Inch Formula

The genesis of our development of FormulaForge was the accumulation of a variety of problems that the founders ran into over the years using Excel. These were epitomized by the time when one of my co-founders, Rob, constructed a formula that wrapped on his 30-inch monitor and had mismatched parentheses. Microsoft Excel, as usual, would not store his formula as originally edited. Instead, it offered a suggestion for a modified version of his formula with matched parentheses. The best thing to do in such a situation is to accept Exel’s suggestion and then debug the formula in the likely event that the suggested version is not correct.

To keep the contents of his sheet as compact as possible, Rob wanted a single, large formula (which he eventually replicated in other rows) in a particular cell. To get there, however, the two of us ended up constructing formulas in other cells that contained subexpressions of the formula he really wanted. We eventually combined these into a single formula (after adjusting for relative references). The whole process took a long time.

That caused us to think about how the process of constructing and editing a complex formula in Microsoft Excel can be very time-consuming. In particular, we felt that the following enhancements would allow formula construction and debugging to happen much more quickly and painlessly.

• Find a way to represent formula text in ways that would reveal its mathematical structure (if it was primarly a computation formula.
• Find a way to represent formula text in a 2-dimensional structure, rather than Excel’s native linear structure, thus making it easier to understand how the formula is evaluated by Excel.
• Find a way to visually show Excel’s evaluation of all subexpressions simultaneously.
• Find a way to relate subexpressions buried within nested IFs to the Boolean conditions tested by those IFs.
• Find a way to substitute descriptive text for subexpressions to make them easier to read without affecting the range names in the Excel file.

Along with another co-founder, Steve, we built an Excel add-in, FormulaForge, to solve these problems. This web site contains considerable descriptive material as well as screencast videos to show you how FormulaForge works.