### Re: Patch for DateTime::Format::W3CDTF to respekt second fragment part

Jonathan Leffler wrote: Or, what happens if there are 10 digits after the decimal point. That's what the substr() is for. Yeah, mostly academic, except I'm working towards a time type (not for Perl per se) that extends down to picoseconds (and up to 10^12 years, too). At least 105 bits, then. TAI64 covers nearly 10^12 years, of course, and the extension TAI64NA goes down to attoseconds in a 128-bit format. What's the concept behind your type? Personally I like to use bignum rational arithmetic, for unlimited resolution. Performance is atrocious with the Perl bignum libraries, unfortunately. -zefram

### Re: Patch for DateTime::Format::W3CDTF to respekt second fragment part

Zefram [EMAIL PROTECTED] wrote: Re: Patch for DateTime::Format::W3CDTF to respekt second fragment part Julian Haupt wrote: +if ($date =~ s/\.(\d+)$// ) +{ + my $fraction = $1; + $p{'nanosecond'} = (1 / $fraction) * 10**9; +} That inversion can't be right. Surely you mathematically want $p{'nanosecond'} = 0.$fraction * 10**9; but actually the nanoseconds member is supposed to be an integer, and it would be better to avoid floating-point arithmetic entirely: $fraction = substr($fraction, 0, 9); $fraction .= 0 x (9 - length($fraction); $p{'nanosecond'} = 0 + $fraction; Beware the picosecond! Or, what happens if there are 10 digits after the decimal point. I've no idea what -3 zeroes looks like, but the answer is unlikely to be correct. Yeah, mostly academic, except I'm working towards a time type (not for Perl per se) that extends down to picoseconds (and up to 10^12 years, too). -- Jonathan Leffler ([EMAIL PROTECTED]) STSM, Informix Database Engineering, IBM Information Management Division 4100 Bohannon Drive, Menlo Park, CA 94025-1013 Tel: +1 650-926-6921Tie-Line: 630-6921 I don't suffer from insanity; I enjoy every minute of it! NB: with effect from 2007-11-28, my address and phone number change to: 4400 N First St, San Jose, CA 95134-1257 Tel: +1 408-956-2436 T/L: 475-2436 smime.p7s Description: S/MIME Cryptographic Signature

### Re: Patch for DateTime::Format::W3CDTF to respekt second fragment part

Julian Haupt wrote: +if ($date =~ s/\.(\d+)$// ) +{ + my $fraction = $1; + $p{'nanosecond'} = (1 / $fraction) * 10**9; +} That inversion can't be right. Surely you mathematically want $p{'nanosecond'} = 0.$fraction * 10**9; but actually the nanoseconds member is supposed to be an integer, and it would be better to avoid floating-point arithmetic entirely: $fraction = substr($fraction, 0, 9); $fraction .= 0 x (9 - length($fraction); $p{'nanosecond'} = 0 + $fraction; -zefram