round() function bug

Scoox — Tue, 24 Apr 2018 07:01:52 GMT

The following expressions produce different results:

round(4) * 1 mm = 4
round(4 mm) = 0

round(5) * 1 mm = 5
round(5 mm)  = 10

round(15.2) * 1 mm = 15
round(15.2 mm)  = 20

As you can see, when the units are inside the brackets, Fusion rounds to the nearest 10 rather than the nearest whole number. This doesn't seem to happen with other functions such as abs(). The workaround is to ensure the units are outside the brackets.

The following screenshot shows the actual results in Fusion:

Why this is a big problem: If the argument to the round() function is a variable, the value assigned to the variable will usually be a dimension with units, e.g. 5 mm, which also causes the problem to happen:

WasherThickness = 0.8 mm
WasherSocketDepth= round(WasherThickness+0.2)  * 1 mm

In this case putting the units outside the brackets doesn't work becasue the variable already has its own units, which would results in mm²:

WasherThickness = 0.8 mm
WasherSocketDepth= round(WasherThickness+0.2) * 1 mm ; Error!

Thanks!

Re: round() function bug

jeff_strater — Tue, 24 Apr 2018 18:22:42 GMT

Yes, this is a known issue. Originally, these functions were assumed to always get "unitless" inputs. So, they did not work correctly with length parameters. This is being actively enhanced to allow them to be units aware. Once this fix is released, "round(4.2 mm)" will work as expected, and return "4.0 mm".

Re: round() function bug

Scoox — Wed, 25 Apr 2018 00:43:28 GMT

Thanks Jeff

topic round() function bug in Fusion Support Forum

round() function bug

Re: round() function bug

Re: round() function bug