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Student Support Forum: 'NDSolve - boundary condition problem' topicStudent Support Forum > General > "NDSolve - boundary condition problem"

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Author Comment/Response
yehuda
03/04/13 1:55pm

As in theory, one should assign a value to the argument only after taking the derivative
D[n[10],x] is the opposite of that
The pattern n[10] is independent of the variable x, so the derivative is zero and when comparing 0 to 0 the result is True

use
n'[10] == 0
or
Derivative[1][n][10] (which is the true code representing n'[10]


so, your code should be

eq = Gx + D[Dif*\!\(
\*SubscriptBox[\(\[PartialD]\), \(x\)]\(n[x]\)\), x] -
Kr (n[x] - n0) == 0;
bcs = {n'[10] == 0, n[0] == n0};
Gx = 5;
Dif = 2;
Kr = 3;
n0 = 1.5;
NDSolve[{eq, bcs}, n[x], {x, 0, 10}]

yehuda

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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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