 Spreadsheet

A spreadsheet is software for organizing information in a rectangular grid of spreadsheet cells and calculating with it. Rows are numbered and columns are lettered: B3 is the spreadsheet cell at column B, row 3. A spreadsheet cell can hold a label, a numerical input, or a spreadsheet formula whose value supplies an output. This brings a mathematical model close to its data: quantities, assumptions and results can be read side by side. The address convention is described in LibreOffice's official help. ^[ref]

The useful idea is to write a relationship once and reuse it across similar rows. Relative spreadsheet references follow each row's data; absolute spreadsheet references retain a shared assumption; mixed spreadsheet references let one coordinate vary while the other stays fixed. Spreadsheet dependency evaluation then computes the resulting spreadsheet formulas. A rectangular layout organizes the model for its reader, while the spreadsheet dependency graph organizes its calculation.