Re: Piecewise functions
- To: mathgroup at smc.vnet.net
- Subject: [mg8906] Re: Piecewise functions
- From: "Stephen P Luttrell" <luttrell at signal.dra.hmg.gb>
- Date: Thu, 2 Oct 1997 22:56:58 -0400
- Organization: Defence Evaluation and Research Agency
- Sender: owner-wri-mathgroup at wolfram.com
Venkateswara Rao Ayyadevara <va2a+ at andrew.cmu.edu> wrote in article
<60s2hp$6mj at smc.vnet.net>...
> I would like to know how to represent piecewise linear functions in
> Mathematica. I tried searching on-line help but could not find any info
> regarding this.
Here is an example notebook showing two different ways of defining a
piecewise linear function (Mathematica 3):
Notebook[{
Cell["Piecewise linear function using Calculus`DiracDelta`:", "Text"],
Cell[BoxData[
\(<< Calculus`DiracDelta`\)], "Input"],
Cell[BoxData[
\(f[x_] := \(-x\)\ UnitStep[\(-x\)] + x\ UnitStep[x]\)], "Input"],
Cell[BoxData[
\(\(Plot[f[x], {x, \(-1\), 1}]; \)\)], "Input"],
Cell["Alternatively you can do it this way:", "Text"],
Cell[BoxData[{
\(g[x_] := \(-x\) /; x \[LessEqual] 0\),
\(g[x_] := x /; x \[GreaterEqual] 0\)}], "Input"],
Cell[BoxData[
\(\(Plot[g[x], {x, \(-1\), 1}]; \)\)], "Input"]
},
FrontEndVersion->"Microsoft Windows 3.0",
ScreenRectangle->{{0, 1024}, {0, 712}},
WindowSize->{496, 604},
WindowMargins->{{0, Automatic}, {Automatic, 0}}
]
--
Stephen P Luttrell
luttrell at signal.dra.hmg.gb
Adaptive Systems Theory 01684-894046 (phone)
Room EX21, DERA 01684-894384 (fax)
Malvern, Worcs, WR14 3PS, U.K.
http://www.dra.hmg.gb/cis5pip/Welcome.html