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A comment on Why does 0.1 and 0.2 = 0.30000000000000004?. Parent comment

Re:Why does 0.1 and 0.2 = 0.30000000000000004? by Kon-Peki on Wednesday February 08, 2023 @03:18PM (#34714334)
If I want to know the monthly payment on a $500,000 mortgage for 30 years at 6%, should I use:

1. Decimal math

2. Binary floating point math

3. Domain knowledge trumps all; it makes no difference

[ Parent | on HN ]
Re:Why does 0.1 and 0.2 = 0.30000000000000004? by gibspaulding on Wednesday February 08, 2023 @04:21PM (#34715379)
Then of course you'll have to work back to compute an APR for that by a crazy iterative formula outlined by the US gov. Which would you use for that process?
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Re:Why does 0.1 and 0.2 = 0.30000000000000004? by meese712 on Wednesday February 08, 2023 @10:32PM (#34719419)
irr? The library we use uses doubles https://github.com/eric-malachias/irr. We also use doubles for the amortization table and doubles for everything.
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Re:Why does 0.1 and 0.2 = 0.30000000000000004? by meese712 on Wednesday February 08, 2023 @10:22PM (#34719364)
Oh hey I work in mortgage! We use plain old doubles for everything and there's some rounds in there and occasionally an exotic round to the nearest 1/8th. Everything ends up matching fine where it needs to.
[ Parent | on HN ]