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Author Comment/Response
Bill Simpson
03/25/13 11:54am

In Response To 'Re: Re: Strange NdSolve solution'
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Discover the wild and wacky world of accuracy and precision in Mathematica?

In[1]:= y[t_]=Exp[2*t]+2*Exp[-t];
s=NDSolve[{z''[t]-z'[t]-2*z[t]==0,z[0]==3,z'[0]==0},z,{t,-100,100}]

Out[2]= {{z->InterpolatingFunction[{{-100.,100.}},<>]}}

In[3]:= y[10]-z[10]/.s[[1]]

Out[3]= -124.973

In[4]:= y[t_]=Exp[2*t]+2*Exp[-t];
s=NDSolve[{z''[t]-z'[t]-2*z[t]==0,z[0]==3,z'[0]==0},z,{t,-100,100}, WorkingPrecision->40, AccuracyGoal->40]

Out[5]=
{{z->InterpolatingFunction[{{-100.0000000000000000000000000000000000000,100.0000000000000000000000000000000000000}},<>]}}

In[6]:= y[10]-z[10]/.s[[1]]

Out[6]= -1.652333477000587644116890291750261192835785`24.098031020518413*^-6

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Subject (listing for 'Strange NdSolve solution')
Author Date Posted
Strange NdSolve solution Jigoro 03/21/13 03:11am
Re: Strange NdSolve solution Bill Simpson 03/22/13 00:52am
Re: Re: Strange NdSolve solution Jigoro 03/23/13 05:29am
Re: Re: Strange NdSolve solution Jigoro 03/25/13 09:03am
Re: Re: Re: Strange NdSolve solution Bill Simpson 03/25/13 11:54am
Re: Re: Re: Re: Strange NdSolve solution Jigoro 03/26/13 05:21am
Re: Re: Re: Re: Re: Strange NdSolve solution Bill Simpson 03/26/13 1:16pm
Re: Re: Re: Re: Re: Re: Strange NdSolve solution jigoro 03/27/13 7:20pm
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