[EMAIL PROTECTED] wrote: > Is this correct?...how MySQL calculate this?...
Yes. Std. Dev = Math.sqrt(sum((val[i]-avg)**2) / count(i)); Verified with a trivial program. > > mysql> select * from temp; > +------------------+ > | cal | > +------------------+ > | 0000000000029.98 | > | 0000000000029.95 | > | 0000000000029.89 | > | 0000000000029.84 | > | 0000000000029.78 | > | 0000000000029.81 | > | 0000000000029.84 | > | 0000000000029.28 | > +------------------+ > 8 rows in set (0.00 sec) > > mysql> > > mysql> select std(cal) from temp; > +----------+ > | std(cal) | > +----------+ > | 0.205240 | > +----------+ > 1 row in set (0.06 sec) > > mysql> > > > > > R.B.Roa > Traffic Management Engineer > PhilCom Corporation > Tel.No. (088) 858-1028 > Mobile No. (0919) 30856267 > > > --------------------------------------------------------------------- > 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 > --------------------------------------------------------------------- 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