andrewgsavage
commented
1 week ago you also need to provide a mass and distance unit
we could change it so the units in the original quantity are used when there aren't any units of a dimension
e: ah maybe I've misunderstood this as it looks like it tried to do what I suggested. is it beacuse it's a 0 magnitude quantity?
if you run this,
a = 0 * UReg.kilogram / UReg.meter ** 3 / UReg.second print(a.to_preferred([UReg.hour]))
it gives error:
pint.errors.DimensionalityError: Cannot convert from 'kilogram / meter 3 / second' ([mass] / [length] 3 / [time]) to 'kilogram 1 / hour / meter 3' ([mass] 1 / [time] / [length] 3)