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These are answers submitted by cosmicstring

There are two unknowns: H(z) and z. There is no clue on how H(z) depends on z. You need either two equations for two unknowns or H(z) itself.

I haven't used the ATLAS package but the free (and extensively used) package grtensorii can do this easily.

It comes with a nice documentation.

I am not sure if integration by parts is applicable here but when you set (not in the Maple format, just for a sketch),




Then v=0 for your assumptions. Thus, u*v-int(v,u) is zero.


But I need to repeat that I am not sure if this is applicable for your case...

From the 1st one,


Put it into the 2nd one:



This one is easy to solve for x. Then use y=4+x for the corresponding y value.

Thank your, it really works for a function but I couldn't manage it for a matrix as a whole.

Let us define a matrix:


Now is there a shortcut to convert this matrix to


Thank you but evalDG is not "enough" for many cases. (My mistake, the example was too trivial.)

evalDG(e[1] &wedge e[2] + e[2] &wedge e[1]);


evalDG(e[1] &wedge e[1]);

                              0 dx ^ dy

but I need just zero.

I tried in many ways after your suggestions and understood that it is impossible to see a solution of the form,


or something similar to this.


Thank you all!

Let us say that I have the following equation:


and I want to find the solution f(u,v)=u*Heaviside(u) or f(u,v)=v*Heaviside(v).

When I pdsolve this equation by


it gives

f(u,v) = _F2(u)+_F1(v)

which is correct but not the solution that I am looking for. I have no idea about the form of the function I need, so I cannot use pdetest for trial and denial. Some HINT for pdsolve may solve the problem as Mr. Richard suggested but I could not find how to write it even for "HINT = any algebraic expression".

Mathematically, I want the solution of the form

f(u*Heaviside(u),v*Heaviside(v)), not f(u,v).



I could not open your worksheet but these lines may be useful:




acer's answer was the key for me because I wanted to eliminate the whole x*Dirac(x)'s in the expression but I have stated my question in the wrong way as I have not thought such a simple answer. But my expression is too long and Joe's answer unlocked the other door for me.

Anyway, Maple is simplifying for more than two hours and I think I will not succeed having a small expression...

Thank you! This really works! Bu now I have a second question:

The function that I have to simplify is very long and it contains many of these u*Dirac(u) type components. So, can I tell Maple to first simplify those ones and then start simplifying the ordinary functions?

I also call the code in Maple by


How should command change in Linux if the directory is home/user/example/mycode.mws ?

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