RE: question (for Mathematica 6!)

*To*: mathgroup at smc.vnet.net*Subject*: [mg75544] RE: [mg75519] question (for Mathematica 6!)*From*: "Owen, HL \(Hywel\)" <h.l.owen at dl.ac.uk>*Date*: Sat, 5 May 2007 05:52:15 -0400 (EDT)

HeavisideTheta[0] is undefined UnitStep[0] gives 1 Their integrals are the same (for example from -1 to 1). And: D[HeavisideTheta[x], x] is DiracDelta[x] Whereas D[UnitStep[x], x] is (-1 - DiscreteDelta[x] + UnitStep[-x] + UnitStep[x])/(1 - DiscreteDelta[x]) Hywel > -----Original Message----- > From: dimitris [mailto:dimmechan at yahoo.com] > Sent: Friday, May 04, 2007 9:09 AM > To: mathgroup at smc.vnet.net > Subject: [mg75519] question (for Mathematica 6!) > > I don't have a copy of Mathematica 6 but having spent much > time reading the online documentation (not only because of > curiosity!) I have one question... > > Can somebody explain me the introduction of the > HeavisideTheta function > > http://reference.wolfram.com/mathematica/ref/HeavisideTheta.html > > in version 6? > > Note that the UnitStep function is still here > > http://reference.wolfram.com/mathematica/ref/UnitStep.html > > Dimitris > > > >