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Comment by ok_computer

2 days ago

Because representing infinity is not possible outside of symbolic logic and isn’t encodable in floats. I think it is a simple numerical reason and not a deeper computer reason.

4 comments

ok_computer

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Sharlin  2 days ago

Well, infinity is totally representable with IEEE 754 floats. For example 1.0/0.0 == +inf, -1.0/0.0 == -inf, but 0.0/0.0 == NaN.

  • amelius  2 days ago

    A smart compiler should be able to figure out a better value for 0/0, depending on context.

    For example:

        for i in range(0, 10):
        print(i/0.0)

    In this case it should probably print +inf when i == 0.

    But:

        for i in range(-10, 10):
        print(i/0.0)

    Now it is not clear, but at least we know it's an infinity so perhaps we need a special value +-inf.

    And:

        for i in range(-10, 10):
        print(i/i)

    In this case, the value for 0/0 can be 1.

    • Sharlin  2 days ago

      Well, it could, but that would be against the spec. The hardware implements IEEE 754, most languages guarantee IEEE 754, and transforming code so that 0.0/0.0 doesn't result in NaN would be invalid.