Re: PiecewiseExpand problem.
- To: mathgroup at smc.vnet.net
- Subject: [mg84530] Re: PiecewiseExpand problem.
- From: "David W.Cantrell" <DWCantrell at sigmaxi.net>
- Date: Wed, 2 Jan 2008 06:57:04 -0500 (EST)
- References: <fl6qon$kkd$1@smc.vnet.net>
jackgold at umich.edu wrote: > I am puzzled by the behavior of PiecewiseExpand. In its simplest > version, my question is this: > > In 1: PiecewiseExpand[UnitStep[x]] > > Out 1: 1 x >= 0 > > Are we to assume from "Out 1" that UnitStep[x] for x < 0 is zero? Sure. Your Out[1] is expressed using Piecewise, so just look at the documentation for Piecewise and note that the default value is 0. > And note the following: > > In 1: PiecewiseExpand[UnitStep[x],x < 0] > > Out 2: 0 > > By the way, PiecewiseExpand[UnitStep[x], -1 < x < 1] returns the > same value as "Out 1". That's correct as well, of course. David