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Problems with NDSolve


I'm having problems with using NDSolve to solve partial differential
equations. Has anyone had any luck with with??
I tried a very simple heat conduction equation as a test with constant
initial temperature and constant temperature at the left face, and a zero 
flux boundary condition at the right face:

soln =NDSolve[{D[y[x,t], t] == D[y[x,t], x, x],
y[0,t]==1, y[x,0]==0, 
Derivative[1,0][y][5,t]==0},
y[x,t], {x,0,5}, {t,0,10}]

I get a strange warning message:

NDSolve::"ibcinc": 
    "Warning: Boundary and initial conditions are inconsistent."

And after plotting the results with

Plot3D[Evaluate[y[x,t] /. First[soln]],
	{x,0,5}, {t,0,10},PlotPoints->30]

get just a flat surface with nothing happening!

Thanks for any help.
...Peter
 
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Peter C. Lichtner	<lichtner at swri.edu>
Southwest Research Institute		http://www.swri.edu/
Center for Nuclear Waste Regulatory Analyses (CNWRA)
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