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From Al Chou <hotfusion...@yahoo.com>
Subject RE: [math] proposed ordering for task list, scope of initial release
Date Tue, 10 Jun 2003 07:54:53 GMT
--- Brent Worden <brent@worden.org> wrote:
> > -----Original Message-----
> > From: Phil Steitz [mailto:steitzp@yahoo.com]
> > Sent: Friday, June 06, 2003 12:21 PM
[deletia]
> > * Exponential growth and decay (set up for financial
> > applications) I think this
> > is just going to be a matter of finding the right formulas to add
> > to MathUtils.
> >  I don't want to get carried away with financial computations,
> > but some simple,
> > commonly used formulas would be a nice addition to the package.
> > We should also
> > be thinking about other things to add to MathUtils -- religiously
> > adhering to
> > th guiding principles, of course.  Al's sign() is an excellent
> > example of the
> > kind of thing that we should be adding, IMHO.
> 
> Things that might be added:
> Average of two numbers comes up a lot.

Do we muddy the class hierarchy by putting such a thing into MathUtils rather
than the stat subtree?


> Something similar to JUnit's assertEquals(double expected, double actual,
> double epsilon).

Is JUnit's license (http://www.opensource.org/licenses/ibmpl.php) Apache
compatible?


> Simple methods like isPositive, isNegative, etc. can be used to make boolean
> expressions more human readable.

I'm willing to build those two on top of sign (I'm so generous with my coding
time, eh? <g>).  Are those two sufficient?  sign treats 0 as positive, which
may not be desirable.


> Some other constants besides E and PI: golden ratio, euler, sqrt(PI), etc.

That would be nice, though we should consider which ones are really needed
generally.  I personally love the lore of constants, of which there are more
than you might imagine (see
http://mathworld.wolfram.com/topics/Constants.html).


> I've used a default error constant several places.  It would be nice to come
> up with a central location for such values.

Or at least define a consistent interface that could be implemented by whatever
needs that.



Al

=====
Albert Davidson Chou

    Get answers to Mac questions at http://www.Mac-Mgrs.org/ .

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