Mathematica 9 is now available
Services & Resources / Wolfram Forums
-----
 /
MathGroup Archive
1994
*January
*February
*March
*April
*May
*June
*July
*October
*November
*December
*Archive Index
*Ask about this page
*Print this page
*Give us feedback
*Sign up for the Wolfram Insider

MathGroup Archive 1994

[Date Index] [Thread Index] [Author Index]

Search the Archive

Solve'ing piecewise defined functions

  • To: mathgroup at yoda.physics.unc.edu
  • Subject: Solve'ing piecewise defined functions
  • From: xinwei at otter.stanford.edu (Sha Xin Wei)
  • Date: Mon, 18 Apr 94 19:00:59 -0700

What's the state of the M-- art using 

Solve[{f1[x]==0, ... , fn[x]==0}, x]
where  fi[] are piecewise linear functions?

Simple-minded usage doesn't work:

	gg[x_] := x + 2 /; x < 0;
	gg[x_] := x -5 /; x >= 0;

	Solve[gg[t]==0,t]
	         (-1)
	{{t -> gg    [0]}}

nor does resorting to numerics,

	f = Interpolation[{{-1,1}, {0-$MachineEpsilon,2}, {0, -5}, 

		{1,-4}}, InterpolationOrder->1]

	Solve[ f[x] == 0, x]
	                                         (-1)
	{{x -> InterpolatingFunction[{-1, 1}, <>]    [0]}}

Xin Wei
Stanford





  • Prev by Date: Spherical Graphics primitive
  • Next by Date: Help in programming
  • Previous by thread: Re: Spherical Graphics primitive
  • Next by thread: Help in programming