Re: bad Mathieu functions
- To: mathgroup at smc.vnet.net
- Subject: [mg108334] Re: bad Mathieu functions
- From: DrMajorBob <btreat1 at austin.rr.com>
- Date: Sun, 14 Mar 2010 05:13:39 -0500 (EST)
> If I specify the precision xplicitly (using tick marks) Mathematica will > keep track of precision (making it a bit slower), and then I'll know the > precision of the result No, because Mathematica's precision calculations generally err on the pessimistic side. That's better than if they were too optimistic, of course. Bobby On Sat, 13 Mar 2010 07:00:09 -0600, becko BECKO <becko565 at hotmail.com> wrote: > > Nevermind. I think I'm getting the point (thanks gekko for detailed > reply). > With MachinePrecision, Mathematica doesn't keep track of precision (in > the interest of speed), so there is no way to issue a warning since > Mathematica doesn't know the precision of the result. If I specify the > precision xplicitly (using tick marks) Mathematica will keep track of > precision (making it a bit slower), and then I'll know the precision of > the result. > > >> Date: Fri, 12 Mar 2010 07:12:04 -0500 >> From: becko565 at hotmail.com >> Subject: [mg108279] Re: [mg108226] bad Mathieu functions >> To: mathgroup at smc.vnet.net >> >> Thanks Carl, Peter and Daniel. >> >> Guess I was too hasty to send that bug report... Though it would be >> useful >> to issue a warning or something (perhaps putting it in the Possible >> Issues >> section of the help on Mathieu functions). I'm kind of falling in love >> with >> Mathematica, so it's reassuring to know that this was my mistake and >> not >> Mathematica's. >> >> Another question. How do I know that WorkingPrecision->50 is enough? >> What if I wanted to Plot all the way to q=100000? > > -- DrMajorBob at yahoo.com