Services & Resources / Wolfram Forums / MathGroup Archive
-----

MathGroup Archive 2007

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

Search the Archive

pl. rectify problem of numerical instaibility

  • To: mathgroup at smc.vnet.net
  • Subject: [mg83657] pl. rectify problem of numerical instaibility
  • From: sandeep kumar <sandeepkumar333 at yahoo.com>
  • Date: Tue, 27 Nov 2007 06:17:46 -0500 (EST)

Please suggest me the solution of this numerical instability. Mathematica Programme:
   
  hm=0.1;
  dmax=5;
  r=dmax*hm;
  di=Abs[x-xi];
  c=r/4;
  w[x_]:=(Exp[-(di/c)^2]-Exp[-(r/c)^2])/(1-Exp[-(r/c)^2])/;di£r;
  w[x_]:=0/; di³r;
  xi=0.6;
  SetOptions[Plot,PlotRange® All];
  Plot[w[x],{x,0,1}];
  dw[x]=D[w[x],x]
   
  I am getting w[x] but dw[x] shows numerical instaibility
   
  Best regards
  sandeep 
   


  • Prev by Date: Re: MapThread over ragged arrays
  • Next by Date: Re: Discrepancy between Integrate and NIntegrate
  • Previous by thread: Re: Stream programming
  • Next by thread: Mathematica 6.0 Desperation