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MathGroup Archive 2003

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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: [mg44570] I have put "==" in every equation I have in NDSolve, why it keeps telling me they are not equations
  • From: Xiaochao Xu <xiaochao at physics.ucsb.edu>
  • Date: Fri, 14 Nov 2003 04:43:17 -0500 (EST)
  • Organization: University of California, Santa Barbara
  • References: <bmqplo$rhb$1@smc.vnet.net> <bmt8eg$87l$1@smc.vnet.net> <3FB43093.4000104@physics.ucsb.edu>
  • Sender: owner-wri-mathgroup at wolfram.com

NDSolve::deqn: "Equation or list of equations expected instead of 0 in the \
first argument

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                v[t, x, y] + Cos[x]*Sin[y]*\[PartialD]\_x v[t, x, y] - 
            Sin[x]*Cos[y]*\[PartialD]\_y v[t, x, y] - 
            Cos[x]*Cos[y]*u[t, x, y] + Sin[x]*Sin[y]*v[t, x, y] - 
            Sin[y]*Cos[y]/c2*
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                t, x, y] + 
            c2*\((\[PartialD]\_x u[t, x, y] + \[PartialD]\_y v[t, x, y])\) + 
            Cos[x]*Sin[y]*\[PartialD]\_x p[t, x, y] == 
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        u[t, x, 1000] == 0, v[t, x, 1000] == 0, p[t, x, 1000] == 0, 
        u[t, x, \(-1000\)] == 0, v[t, x, \(-1000\)] == 0, 
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