# User Portlet

Discussions |
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Hi Frank, I am pretty convinced now that the problem I had was not one of (near) duplicates but one of ordering. After I saw that a Union[] operation of the basic data solved the problem, I subsequently repeated the calculation, using Sort[]... |

Huang, You're right on that point. The plot should come out OK in spite of the error in the integration. My comment was too hasty. RenĂ© |

Stven, Point 1: In reply to your question how to make a grid in Mathematica I have attached a simple Notebook example for you. The most important ingredient is the Table-function. That is THE way for making vectors or matrices or objects of even... |

David, This explanation is very helpful. Thanks a heap. Sometimes Mathematica makes me think of the famous Einstein quote (in his refutation of the probabilistic interpretation of Quantum Mechanics): "God is subtle but he is not malicious".... |

Dear Gianluca, dear Frank, gents, You were both "spot-on". 1. The unboundedness of the domain was the problem. 2. And I would quickly have found that out if I had simplified the problem. For your entertainment I enclose the "corrected"... |

David's suggestion was the easiest and fastest solution for me. Thanks a heap. RenĂ© Samson |

Dear Craig, In the attachment please find my "working solution" for the Laplace eqn in a spherical shell domain. I put "working solution" in quotation marks because obviously this isn't yet a correct solution. I suspect that I have to refine the... |