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 Author Comment/Response Luka 03/04/13 06:19am Hi! I am trying to solve a simple eguation with NDSolve and get the following error message: NDSolve::deqn: Equation or list of equations expected instead of True in the first argument {5-3 (-1.5+n[x])+2 (n^\[Prime]\[Prime])[x]==0,{True,n[0]==1.5}}. >> My code is: eq = Gx + D[Dif*\!\( \*SubscriptBox[\(\[PartialD]\), \(x\)]\(n[x]\)\), x] - Kr (n[x] - n0) == 0; bcs = {D[n[10], x] == 0, n[0] == n0}; Gx = 5; Dif = 2; Kr = 3; n0 = 1.5; NDSolve[{eq, bcs}, n[x],{x, 0, 10}] Output: NDSolve[{5 - 3 (-1.5 + n[x]) + 2 (n^\[Prime]\[Prime])[x] == 0, {True, n[0] == 1.5}}, n[x], {x, 0, 10}] The values are not real. I am asking why does my first boundary condition evaluate to True? I have to solve much more complicated differential equation but there is unexpected problem in the beginning. Thank you! Best regards, Luka URL: ,

 Subject (listing for 'NDSolve - boundary condition problem') Author Date Posted NDSolve - boundary condition problem Luka 03/04/13 06:19am Re: NDSolve - boundary condition problem yehuda 03/04/13 1:55pm Re: Re: NDSolve - boundary condition problem Luka 03/04/13 3:52pm
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