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July 10, 2001 18:56Subject:

Re: [DOC PATCH bleadperl] detypo Math::BigInt docsMessage ID:

200107102246.f6AMkc914615@xena.tops.net-----BEGIN PGP SIGNED MESSAGE----- Moin, On 10-Jul-01 Philip Newton tried to scribble about: > On 10 Jul 01, at 15:52, John Peacock wrote: > >> 0 cannot ever be positive or negative by itself (that is truly the >> definition >> of positive {>0} and negative {<0} ). > > True; however, as I understand it, IEEE floating-point arithmetic > allows for there to be positive and negative zero since it uses a sign- > magnitude representation. And Math::Big* objects also store the sign > separately, so they can (potentially) have positive and negative > zeroes. But (in praxis) there is no -0 in MBI. ;) (And I am glad for that, surely) >> Therefore 0/0==0 is a sensible default (since 0/num == 0 for all >> other num). > > On the other hand, if a/b==c, then b*c == a. This holds for 10/5==2 --> > 5*2==10, but not if you posit 0/0==0, since 0*0==0, but 5*0==0 as well, > so one could argue that 0/0 should be 5. This argument holds for any > possible result. So if 0/0 has any one value, it has to be one that's > specially defined; NaN makes sense to me for this. Agreed. > (And what do you think is 0**0? 0**n == 0 for all positive n, but n**0 > == 1 for all positive n.... Presumably, 0**0 is also NaN, then.) 0 ** 0 is 1, be definition. Not my fault ;) (I got some sensible arguments for this..you can't argue with sensible arguments from sensible people ;) Best wishes, Tels - -- perl -MMath::String -e 'print \ Math::String->from_number("215960156869840440586892398248"),"\n"' http://bloodgate.com/thief/ Thief - The Dark Project http://bloodgate.com/perl My current Perl projects http://freedomforlinks.de Fight for your right to link. PGP key available on http://bloodgate.com/tels.asc or via email -----BEGIN PGP SIGNATURE----- Version: 2.6.3i Charset: latin1 iQEVAwUBO0tkVXcLPEOTuEwVAQGKSwf+I6yOWj0RqYKBR2BBJ0myM/Gd4liFRA8x 7caT8C6BCMg945EzK6vbUpiPgjTOoPLmMDMDv3hlfSuVb81l/Lvy3x6ckQnX/csQ 7yhrfCUBlwuJWOf3EcMfaI6LvYCFBN9DQKbztpdpNCvKbXODRYPUyslAwiNo0ZQm ggmXs9o3kPmhiIQWgL7Pwpgpw/Pg2kDmoFI81y9uddEq7FFyYIcDbeIsrIi1BniQ xNyyvFa2xsH6LXVuB1ro1FaIeOu/DlkWBANLoUQbI77baPJ6OCNR9SnDUmoKYjbn rqS/NCOI6Ljqfjj8hziPyvfQ6O3B0ysSFQ2j1oUleTFl9/TlxMA5iA== =g2kJ -----END PGP SIGNATURE-----Thread Previous | Thread Next

- [DOC PATCH bleadperl] detypo Math::BigInt docs by Philip Newton
- Re: [DOC PATCH bleadperl] detypo Math::BigInt docs by John Peacock
**Re: [DOC PATCH bleadperl] detypo Math::BigInt docs**by Tels- Re: [DOC PATCH bleadperl] detypo Math::BigInt docs by Tels
- Re: [DOC PATCH bleadperl] detypo Math::BigInt docs by Tels
- Re: [DOC PATCH bleadperl] detypo Math::BigInt docs by Philip Newton
- Re: [DOC PATCH bleadperl] detypo Math::BigInt docs by John Peacock
- Re: [DOC PATCH bleadperl] detypo Math::BigInt docs by Philip Newton
- Re: [DOC PATCH bleadperl] detypo Math::BigInt docs by Jarkko Hietaniemi

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