* Gordon > This round discussion has nothing to do with floating point > approximations.
well... > Most round routines are statistically biased on the high side. The MySQL > round is statistically correct. The more accurate rounding rule is As far as I can tell, there is no "MySQL round"... as the behaviour is different on different platforms. From my original post in this thread: > solaris: > > mysql> select round(0.05,1),round(0.15,1),round(0.25,1),round(0.35,1); > +---------------+---------------+---------------+---------------+ > | round(0.05,1) | round(0.15,1) | round(0.25,1) | round(0.35,1) | > +---------------+---------------+---------------+---------------+ > | 0.0 | 0.2 | 0.2 | 0.4 | > +---------------+---------------+---------------+---------------+ > 1 row in set (0.00 sec) > > Sometimes it rounds up, sometimes it rounds down... > > win2k: > > mysql> select round(0.05,1),round(0.15,1),round(0.25,1),round(0.35,1); > +---------------+---------------+---------------+---------------+ > | round(0.05,1) | round(0.15,1) | round(0.25,1) | round(0.35,1) | > +---------------+---------------+---------------+---------------+ > | 0.0 | 0.1 | 0.2 | 0.3 | > +---------------+---------------+---------------+---------------+ > 1 row in set (0.00 sec) The solaris behaviour seems to match your description of an accurate rounding. (version 3.23.39-log on solaris and 3.23.30-gamma on win2k) The explanation I got was that this depends on the floating point routines in the C lib, and maybe even the math processor... -- Roger query --------------------------------------------------------------------- Before posting, please check: http://www.mysql.com/manual.php (the manual) http://lists.mysql.com/ (the list archive) To request this thread, e-mail <[EMAIL PROTECTED]> To unsubscribe, e-mail <[EMAIL PROTECTED]> Trouble unsubscribing? Try: http://lists.mysql.com/php/unsubscribe.php
