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One for the Maple bugkeepers. There seems to be a problem with DEtools[initialdata] -- in some circumstances the output initial data is wrong -- missing "D" operators. For instance, suppose one has a PDE system with dependent variables u(x), v(x,y). Then initialdata works. But if the PDE has dependent variabls u(x), v(y,x) then initialdata returns incorrect results.

For a minimal example, consider the following code... 

    with(DEtools):
    initialdata([diff(u(x),x,x)=0, v(x,y)=0]);
which gives correct initial data, namely: 
    table([Finite = [u(x[0]) = _C1, D(u)(x[0]) = _C2], Infinite = []])

Now alter the system so that the arguments are (y,x) instead of (x,y)... 

    initialdata([diff(u(x),x,x)=0, v(y,x)=0]);
This gives initial data 
    table([Finite = [u(x[0]) = _C1, u(x[0]) = _C2], Infinite = []])
which is wrong -- a "D" operator went missing.

The same bug manifests even if the system is rifsimp'ed first, for instance 

    initialdata(rifsimp([diff(u(x),x,x)=0, v(y,x)=0]));

BTW I'm running Maple 10.03.

Ian.
differential-equation detools

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