Floats internally use numerator and denominator (float.as_integer_ratio().) It makes no sense to have sign and mantissa while displaying numerator and denominator. Perhaps a redo of the class? I believe fractions should be the standard, and just keep the ieee754 floats as a side option. On Sun, May 31, 2015 at 7:37 PM, <python-ideas-request@python.org> wrote:

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Today's Topics:

1. Python Float Update (u8y7541 The Awesome Person) 2. Re: Python Float Update (Nathaniel Smith)

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Message: 1 Date: Sun, 31 May 2015 19:25:46 -0700 From: u8y7541 The Awesome Person <surya.subbarao1@gmail.com> To: python-ideas@python.org Subject: [Python-ideas] Python Float Update Message-ID: < CA+o1fZONRG_dZzct_VZwcUvtwD-5rJ6zOFxNR34jWFrpUXiw9Q@mail.gmail.com> Content-Type: text/plain; charset="utf-8"

Dear Python Developers:

I will be presenting a modification to the float class, which will improve its speed and accuracy (reduce floating point errors). This is applicable because Python uses a numerator and denominator rather than a sign and mantissa to represent floats.

First, I propose that a float's integer ratio should be accurate. For example, (1 / 3).as_integer_ratio() should return (1, 3). Instead, it returns(6004799503160661, 18014398509481984).

Second of all, even though 1 * 3 = 3 (last example), 6004799503160661 * 3 does not equal 18014398509481984. Instead, it equals 1801439850948198**3**, one less than the value in the ratio. This means the ratio is inaccurate, as well as completely not simplified.

[image: Inline image 1]

Even if the value displayed for a float is a rounded value, the internal numerator and denominator should divide to equal to completely accurate value.

Thanks for considering this improvement!

Sincerely, u8y7541