The tilde ~ is an approximation indicator... so 1.4mm >>> ~1mm IF your number of dp's in the Model > Units is set too low.
You get this using .to_l etc.
You can always get a distance or xyx value in inches [the default base units] and convert them to something else with methods like .to_mm...
You can also convertfloars to a fixed number of dp's using sprintf() etc...
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