这是计算机算术的预期结果.它遵循特定规则，例如 IEEE 754，这可能与您所学的数学不匹配在学校.

This is to be expected with computer arithmetic. It is following particular rules, such as IEEE 754, that probably don't match the math you learned in school.

如果这实际上很重要，请使用 Python 的十进制类型.

If this actually matters, use Python's decimal type.

示例:

from decimal import Decimal, Context
ctx = Context(prec=20)
two = Decimal(2)
ctx.divide(ctx.power(two, Decimal(31)).ln(ctx), two.ln(ctx))