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Date: Tue, 3 Oct 2023 18:13:11 +0900
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Cc: Jorg Sowa <jorg.sowa@gmail.com>,
 PHP internals <internals@lists.php.net>
To: Pierre Joye <pierre.php@gmail.com>
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 <89C362E8-1D89-4F43-AE01-FAA286CC8343@sakiot.com>
 <CAEZPtU4a04Bd7zSvoCcX4=KtmVo4ODhZJBXKjsBbkb5zcQRARg@mail.gmail.com>
Subject: Re: [PHP-DEV] [RFC] [Discussion] Adding bcround, bcfloor and bcceil
 to BCMath
From: saki@sakiot.com (Saki Takamachi)

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> yes, they do, as do almost all floating points implementation.=20
>=20
> Memory limited float values and their respective operations are still =
useful in many areas, but financial values and the likes. Scaled =
integers are the way for accuracy.=20
>=20
>=20
> Also, side note, gmp recommends to rely on https://www.mpfr.org/ for =
accurate FP operations

Hi

This seems to be a floating point number with extremely high precision =
compared to regular long doubles. However, as you say, even though the =
accuracy is very high, errors still occur. (the error is so small that =
it almost never becomes a problem.)

By its very nature, BCMath does not introduce any errors. It is =
debatable whether floating point calculations in GMP can play the role =
of BCMath.

Regards.

Saki=

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