Search All of the Math Forum:
Views expressed in these public forums are not endorsed by
NCTM or The Math Forum.



Re: Multiplication by 0: nonzero in versions 8 and 9
Posted:
Jun 16, 2013 5:14 AM


In fact, the Mathematica behavior you observe in later versions, while possibly disconcerting on strictly mathematical grounds, is reassuring on software consistency grounds. Thus, the 9.0.1 documentation page tutorial/ExactAndApproximateResults says:
"Whenever you give a number with an explicit decimal point, Mathematica produces an approximate numerical result [for a calculation involving that number]."
Personally, I would be unhappy if I did a calculation some of whose numbers were approximate yet whose answer gave a misleading exact answer. On Jun 15, 2013, at 4:23 AM, Sotirios Bonanos <sbonano@inp.demokritos.gr> wrote:
> Hello , > > I have noticed that in all Mathematica versions <8, multiplying a real or complex number by the integer 0 gives 0, but in versions 8 and 9 > > Times[0, 0.567] gives 0. > > and > > Times[1.23 + I 2.45, 0] gives 0. + 0. I > > I don't know what prompted this change but it is definitely wrong: the zero property of multiplication holds for real and complex numbers also (see https://en.wikipedia.org/wiki/Multiplication#Properties) . > > Sotirios Bonanos > http://www.inp.demokritos.gr/~sbonano/ >
 Murray Eisenberg murray@math.umass.edu Mathematics & Statistics Dept. Lederle Graduate Research Tower phone 413 5491020 (H) University of Massachusetts 413 5452838 (W) 710 North Pleasant Street fax 413 5451801 Amherst, MA 010039305



