Unresolved symbolic integral - How to solve numerically?

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I need to solve a complex 1st order PDE with 3 spatial inputs (x,y,z) and two angles (theta,phi). Only spatial partials are involved in the equation. I eliminated the spatial partials with the method of characteristics and now I am left with an ODE. The solution however involves indefinite integrals that the symbolic toolbox cannot solve (and I definitely cannot solve on my own).
Can I somehow use one of the 'integral' function to solve these indefinite integrals? My problem with that approach is that I don't know what limits of integration to provide to the function.
Alternatively I would consider the PDE toolbox to solve directly the PDE, but it does not solve 1st order PDEs to my knowledge.
  2 Comments
Torsten
Torsten on 6 Mar 2017
By applying boundary conditions to your PDE, your indefinite integrals should change to definite ones.
Best wishes
Torsten.
Vasilis Andriopoulos
Vasilis Andriopoulos on 10 Mar 2017
I found out that a symbolic solution is not possible for this problem without unwanted simplifications. Thank you for your answer.

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Accepted Answer

John D'Errico
John D'Errico on 5 Mar 2017
No. You cannot use a numerical integration tool (integral) to solve indefinite integrals, and certainly not symbolic ones.
Not all problems have solutions. The art of mathematics is to find a way to solve intractable problems, instead of throwing them at a computer and hoping the computer can solve it for you. Computers are great at solving messy problems that are tractable, if only you had a vast amount of time and patience.

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