Re: I have put "==" in every equation I have in NDSolve, why it keeps telling me they are not equations
- To: mathgroup at smc.vnet.net
- Subject: [mg44587] Re: I have put "==" in every equation I have in NDSolve, why it keeps telling me they are not equations
- From: drbob at bigfoot.com (Bobby R. Treat)
- Date: Sat, 15 Nov 2003 02:05:15 -0500 (EST)
- References: <bmqplo$rhb$1@smc.vnet.net> <bmt8eg$87l$1@smc.vnet.net> <3FB43093.4000104@physics.ucsb.edu> <bp299p$38b$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
My Mathematica 5.0 kernel doesn't seem to have that problem. I'd suggest
eliminating the new-lines embedded in the equation list, as that can
sometimes lead to problems.
I get this error instead:
NDSolve::underdet: There are more dependent variables, {p[y, t, x],
u[y, t, \
x], v[y, t, x]}, than equations, so the system is underdetermined.
Bobby
Xiaochao Xu <xiaochao at physics.ucsb.edu> wrote in message news:<bp299p$38b$1 at smc.vnet.net>...
> NDSolve::deqn: "Equation or list of equations expected instead of 0 in the \
> first argument
>
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