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Subject: PDEPE boundary conditions ul equals ur
Date: Fri, 7 Feb 2014 12:28:09 +0000 (UTC)
Organization: Hanoi National Univ of Science
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Hi all,

I am trying to solve a pdepe of the form: 
du/dt = A*du/dx;

However, the boundary condition is: u(xl,t) = u(xr,t) for all t.

I tried to put 
ql = -1/A;
qr = -1/A;
pl = ul;
pr = ur;

then the code some how works but this does not satisfy the boundary condition that I want. 

I tried to put them all the 0 then the code show the error:
Error using daeic12 (line 77)
This DAE appears to be of index greater than 1.

Could you please advise me in this case, any help will be much appreciated.

Best regards,
Trung