30.09.21 10:07, Jeff Allen пише:
>>>> from decimal import Decimal
>>>> Decimal('-3.14') // Decimal('Infinity')
> Decimal('-0')
You do not need an infinity to see the difference.
>>> Decimal('3.14') % Decimal('2')
Decimal('1.14')
>>> Decimal('3.14') % Decimal('-2')
Decimal('1.14')
>>> Decimal('-3.14') % Decimal('2')
Decimal('-1.14')
>>> Decimal('-3.14') % Decimal('-2')
Decimal('-1.14')
Decimals use a different rule than integers and floats: the modulus has
the same sign as the dividend. It was discussed using this rule for
floats (perhaps there is even FAQ or HOWTO for this), there are
advantages of using it for floats (the result is more accurate). But the
current rule (the modulus has the same sign as the divisor) is much much
more convenient for integers, and having different rules for integers
and floats is a source of bugs.
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