Re: Multiplication by 0: non-zero in versions 8 and 9

*To*: mathgroup at smc.vnet.net*Subject*: [mg131185] Re: Multiplication by 0: non-zero in versions 8 and 9*From*: Bob Hanlon <hanlonr357 at gmail.com>*Date*: Sun, 16 Jun 2013 05:17:35 -0400 (EDT)*Delivered-to*: l-mathgroup@mail-archive0.wolfram.com*Delivered-to*: l-mathgroup@wolfram.com*Delivered-to*: mathgroup-outx@smc.vnet.net*Delivered-to*: mathgroup-newsendx@smc.vnet.net*References*: <20130615082348.A15416A72@smc.vnet.net>

Use of inexact numbers produces inexact results (which can be handled with Rationalize or Chop). Use of exact numbers produes exact results. Times[1.23 + I 2.45, 0] // Rationalize 0 Times[1.23 + I 2.45, 0] // Chop 0 Times[123/100 + I 245/100, 0] 0 Times[1.23 + I 2.45 // Rationalize, 0] 0 Bob Hanlon On Sat, Jun 15, 2013 at 4:23 AM, Sotirios Bonanos <sbonano at 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/ > > >

**References**:**Multiplication by 0: non-zero in versions 8 and 9***From:*Sotirios Bonanos <sbonano@inp.demokritos.gr>