Re: avoid spurious vertical segment in step function plot
- To: mathgroup at smc.vnet.net
- Subject: [mg23395] Re: [mg23327] avoid spurious vertical segment in step function plot
- From: Murray Eisenberg <murray at math.umass.edu>
- Date: Fri, 5 May 2000 02:07:35 -0400 (EDT)
- Organization: Mathematics & Statistics, Univ. of Mass./Amherst
- References: <8erac6$hk2@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Another interesting and useful solution. Thanks.
BobHanlon at aol.com wrote:
>
> This may look familiar ...
>
> plt = Plot[
> UnitStep[x] - UnitStep[x - 1] + UnitStep[x - 2] -
> UnitStep[x - 3], {x, -1, 4}, Frame -> True, Axes -> False,
> PlotRange -> {-.2, 1.2}];
>
> threshold = 0.5;
>
> Show[plt //. {Line[{start___, {x1_, y1_?(# < threshold &)}, {x2_,
> y2_?(# > threshold &)}, end___}] :>
> Sequence[Line[{start, {x1, y1}}], Line[{{x2, y2}, end}]],
> Line[{start___, {x1_, y1_?(# > threshold &)}, {x2_,
> y2_?(# < threshold &)}, end___}] :>
> Sequence[Line[{start, {x1, y1}}], Line[{{x2, y2}, end}]]}];
>
> There is probably some way to work these two rules into one; however, it
> didn't leap immediately to mind.
>
> In a message dated 5/2/2000 1:01:33 AM, murray at math.umass.edu writes:
>
> >Several packages available from MathSource deal with eliminating the
> >spurious parts of plots of discontinuous functions across vertical
> >asymptotes.
> >
> >Is there some simple way of dealing with the similar problem of
> >eliminating the spurious vertical line segment in plotting a function
> >with jumps -- for example, in the following?
> >
> > Plot[UnitStep[x], {x, -1, 1}]
> >
>
> Bob
>
> BobHanlon at aol.com
--
Murray Eisenberg murray at math.umass.edu
Mathematics & Statistics Dept. phone 413 549-1020 (H)
Univ. of Massachusetts 413 545-2859 (W)
Amherst, MA 01003-4515