I need a comparison like the latter which answers “true” instead of false: 48.038385826771666.to_l ~ 1220mm 48.038385826771666.to_l == 1220.mm false SketchUp has done some weird things with numbers. Even when you loop them through floats, they don’t lose their approximate-ness: 48.038385826…

When SketchUp compares lengths (numbers of Length class), SketchUp considers its internal tolerance. This tolerance is important because geometric computations on computers lead to small numerical inaccuracies (rounding, truncation) that accumulate over time and would cause conflicts (coordinates n…

The tilde however does not correspond to the internal tolerance but to the number of digits that you have set in Model Info as display accuracy. The two lengths may truely be different. You could round them to the same number of digits behind the decimal point (using a helper function by getting fr…

What ‘tolerance’ do you want ? Let’s assume ±1mm tol = 1.mm (48.038385826771666.to_l - 1220.mm).abs <= tol the second line returns true if within tolerance [in this example ±1mm] or false if outside it…

“Approximate-ness” isn’t some kind of internal state of Length objects. The “~” mark is added when the Length is converted to a String, in the case it’s very close to the numerical representation but not close enough for them to be considered the same using SketchUp’s internal tolerance. If “48.038…

How to compare approximate values

Developers

prescod March 19, 2017, 10:34pm 6

Thanks for clarifying everyone. I understand what is going on inside SketchUp better and that helps me to tailor my solution.

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How to compare approximate values

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