Round Double: Building Sum of rounded doubles causes inconsistencies


while working on the latest Just Knime It Challenge I noticed that the Round Double Node seems to not quite round to the decimal as instructed causing issues further down the workflow i.e. when visualizing the data.

Yes, I am aware of the Number Formatter but this is purely about rounding up, inspecting the results which look fine but upon calculating the sum, ending up with slight deviations.

With Round Double

Visualization issue

Without Round Double


Hi @mwiegand ,

I fear this is they way floating point numbers work. Since they are base two, they cannot represent many decimal values exactly. There is a forum thread requesting support for a decimal data type Add a "fixed decimal" currency friendly data type , you can leave a vote there.

Best regards,