-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Hi James,
I would say that 0.333 (in a scientific context) implies that I am confident about this number up to the third decimal point, i.e. 0.3325 <= x <= 0.3334. This gives you an idea of the precision. 1/3 is not a scientific format, but a mathematical one, unless for some constraint you know that value is exactly 1/3, then there is no error associated with it. Cheers, Tim On 07/23/2014 09:57 PM, James Holton wrote: > > Where is it written that compactness of representation and > accuracy/precision are the same thing? Is 1/3 more or less precise > than 0.333 ? > > If mmCIF were a binary floating-point format file, there would be > more "decimal places" in the precision of the stored value for the > unit cell, despite fitting into only 4 bytes instead of the 13 > bytes of text some seem offended to see below. Would that be > better? Or worse? > > -James Holton MAD Scientist > > On 7/22/2014 4:01 AM, Bernhard Rupp wrote: >> >> I am just morbidly curious what program(s) >> deliver/mutilate/divine these cell constants in recent cif >> files: >> >> data_r4c69sf >> >> # >> >> _audit.revision_id 1_0 >> >> _audit.creation_date ? >> >> _audit.update_record 'Initial release' >> >> # >> >> _cell.entry_id 4c69 >> >> _cell.length_a 100.152000427 >> >> _cell.length_b 58.3689994812 >> >> _cell.length_c 66.5449981689 >> >> _cell.angle_alpha 90.0 >> >> _cell.angle_beta 99.2519989014 >> >> _cell.angle_gamma 90.0 >> >> # >> >> Maybe a little plausibility check during cif generation might be >> ok >> >> Best, BR >> >> PS: btw, 10^-20 meters (10^5 time smaller than a proton) in fact >> seriously challenges the Standard Model limits.... >> >> ---------------------------------------------------------------------------------------- >> >> >> >> Bernhard Rupp >> >> k.-k. Hofkristallamt >> >> Crystallographiae Vindicis Militum Ordo >> >> b...@ruppweb.org <mailto:b...@ruppweb.org> >> >> b...@hofkristallamt.org <mailto:b...@hofkristallamt.org> >> >> http://www.ruppweb.org/ >> >> ----------------------------------------------------------------------- >> > >> > - -- - -- Dr Tim Gruene Institut fuer anorganische Chemie Tammannstr. 4 D-37077 Goettingen GPG Key ID = A46BEE1A -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (GNU/Linux) Comment: Using GnuPG with Icedove - http://www.enigmail.net/ iD8DBQFT0NofUxlJ7aRr7hoRAjEHAKDHJB/iHYgx6qJyr/k3U5TI5y6YSACguJli rWda+amIYdVWnT40WGw8dPA= =taoT -----END PGP SIGNATURE-----
