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> But time is not the fundamental axis in a spreadsheet I’ve worked with lots of financial projection and reportinf spreadsheet, and time has usually been the,

> But time is not the fundamental axis in a spreadsheet I’ve worked with lots of financial projection and reportinf spreadsheet, and time has usually been the, or at least a, fundamental axis. > but the calculations don't step through time, day by day (or weekly/monthly/hourly) like they do in other simulation systems. They... absolutely do, if the underlying view that the sheet is built around is a sequence of time steps. A workbook with a control plane sheet or sheets with starting values and a grid of input variables in rows and timesteps in columns with an output sheet with output variables in rows and timesteps in columns, where each output row has a formula taking into account outputs in earlier timesteps and inputs in the same or earlier timesteps is, IME, a fairly common way to construct a modeling tool using spreadsheet software.

jonnylegs 1y ago
You’re right... it’s absolutely possible to build time-step models in spreadsheets. The distinction I’m trying to make is that in spreadsheets, time is something the modeler has to impose and maintain. It’s not native to the system. Every dependency and assumption is hard-coded into formulas that only the creator fully understands. That makes the model powerful, but also fragile and hard to scale. In contrast, (and the whole thesis of the software we've built) simulation and event-based approaches treat time as a first-class citizen. The engine itself steps through each day, week, or month, checking which events are active and applying their effects. Instead of hand-building those mechanics each time, you snap together reusable logic blocks. For the modeler, it’s less about “can we do this?” (because spreadsheets can do almost anything) and more about “should we keep reinventing the wheel, or use a framework that makes time and dependencies explicit by design?”

jonnylegs 1y ago

You’re right... it’s absolutely possible to build time-step models in spreadsheets. The distinction I’m trying to make is that in spreadsheets, time is something the modeler has to impose and maintain. It’s not native to the system. Every dependency and assumption is hard-coded into formulas that only the creator fully understands. That makes the model powerful, but also fragile and hard to scale. In contrast, (and the whole thesis of the software we've built) simulation and event-based approaches treat time as a first-class citizen. The engine itself steps through each day, week, or month, checking which events are active and applying their effects. Instead of hand-building those mechanics each time, you snap together reusable logic blocks. For the modeler, it’s less about “can we do this?” (because spreadsheets can do almost anything) and more about “should we keep reinventing the wheel, or use a framework that makes time and dependencies explicit by design?”