today I'm thinking about the "don't use floating point for money" advice I hear all the time. It obviously has a lot of truth to it.
But -- Excel/Google Sheets uses floating point for all of its calculations, people use spreadsheets for money calculations all the time, and it generally seems to work just fine -- the results get rounded for display.
So I'm trying to figure out if there's a more nuanced guideline than "never use floating point for money".
@b0rk My first reaction to this is kinda condescending, which is just “Don’t use excel or google sheets for money if you actually need accuracy” and I’m debating how much that’s genuine advice I’d stand behind.
Possibly losing pennies or dollars or thousands of dollars to rounding errors is gonna be small potatoes compared to other errors caused by the difficult-to-debug nature of spreadsheets (see for example https://www.science.org/content/article/one-five-genetics-papers-contains-errors-thanks-microsoft-excel).
@simrob I'm struggling to see a real world use case where you would lose even 1 cent to a floating point error in a spreadsheet
like I'm sure it exists! But I personally do not know how to make a spreadsheet that does a remotely realistic calculation that has such an error
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