Mathematica 9 is now available
Student Support Forum
-----
Student Support Forum: 'NDSolve' topicStudent Support Forum > General > "NDSolve"

< Previous Comment | Next Comment >Help | Reply To Comment | Reply To Topic
Author Comment/Response
Bill Simpson
12/03/12 01:12am

In Response To 'Re: Re: Re: Re: NDSolve'
---------
I apologize for my mistakes.

Here is what I have at the moment

In[1]:= n=2; m= .3; κ=2; l= -1.1; ti=0; ts=1000; ph= .8; phd=2.1; xi=3;
NDSolve[{2x''[t]/x[t]+(x'[t]/x[t])^2 + κ (y'[t]^2/2 - n Exp[m y[t]]) + κ(l y[t]^3 y'[t])/(3 x[t]^2)==0, y''[t] + 3(x'[t]/x[t])y'[t] + n m Exp[m y[t]] + (l x'[t] y[t]^3)/x[t]^3==0, y[ti]==ph, x[ti]==xi, y'[ti]==phd, x'[ti]== -xi Sqrt[κ/3]Sqrt[((y'[ti]/2)^2 + n Exp[m y[ti]])}, {x, y}, {t, ti, ts}]\)

From In[1]:= Solve::incnst: Inconsistent or redundant transcendental equation. After reduction, the bad equation is 12-50 Log[E^(3<<1>>/10]== 0.
...

And it is that warning message that worries me. I am guessing that is not a message to ignore. Unfortunately, as it says, this is after NDSolve and Solve have already made changes to your original equations and this was why I could not pinpoint exactly where the problem was.

Be careful with this because it is easy to introduce errors when trying to scrape-n-paste Mathematica output into a readable form here.


URL: ,

Subject (listing for 'NDSolve')
Author Date Posted
NDSolve Amir Hadi Zi... 11/29/12 4:39pm
Re: NDSolve Bill Simpson 11/29/12 6:43pm
Re: Re: NDSolve Amir Hadi Zi... 12/01/12 02:15am
Re: Re: Re: NDSolve Bill Simpson 12/01/12 1:36pm
Re: Re: Re: Re: NDSolve Amir Hadi Zi... 12/02/12 00:58am
Re: Re: Re: Re: Re: NDSolve Bill Simpson 12/03/12 01:12am
Re: NDSolve Michael 12/02/12 09:22am
Re: Re: NDSolve Amir Hadi Zi... 12/03/12 01:25am
< Previous Comment | Next Comment >Help | Reply To Comment | Reply To Topic