Here’s a strange math issue: This specifical and simple math operation is giving me an incorrect, though very little result 0.85 - (3.88 - (0.23+0+2.57+0.23)) [image] If you’re wandering why these numbers… it’s of course part of a debug process. These are numbers from different variables. I tho…

Maybe change units If a number is divided and the outcome is very, very small, this happens

That’s what I was thinking before manually inputing the numbers, but now they’re just sums and subtractions and the error is still there…

As Marcel said, this is pretty common when dealing with very small numbers or a value that has a different level of precision than Dynamo. Just round to a reasonable precision and they should clear up.

Welcome to the world of floating point arithmetic issues. You are basically coming up against the ‘after adding a teaspoon of water into a swimming pool you still have a swimming pool’s worth of water’ example given here: Floating point inaccuracy examples - Stack Overflow

Similar post here. [image] Wrong calculation lot's of digits Lists-Logic I don’t think it’s wrong. It has to do with the way that double-precision floating point numbers work. This isn’t unique to Dynamo. https://www.exploringbinary.com/why-0-point-1-does-not-exist-in-fl…

Simple math operation failing

DesignScript

mzjensen January 8, 2022, 4:43pm 6

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Simple math operation failing

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