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 2d comment Package for symbolic computation of christoffel symbols and parallel transports in Riemannian geometry, given the metric If you were a physicist specializing in general relativity, I would suggest xAct with xCoba for the Christoffels, but it requires extensive knowledge of differential geometry. There exist less complicated packages, but I have no experience with them. Apr23 accepted Express block matrix in terms of matrix basis Apr16 revised Express block matrix in terms of matrix basis deleted 30 characters in body Apr16 comment Express block matrix in terms of matrix basis Thanks, this is very close to what I was looking for. Please check my answer and feel free to add the changes I made to yours, so that I accept yours and delete mine. Apr16 answered Express block matrix in terms of matrix basis Apr16 awarded Curious Apr15 revised Express block matrix in terms of matrix basis added 8 characters in body Apr15 revised Express block matrix in terms of matrix basis added 1113 characters in body Apr15 revised Express block matrix in terms of matrix basis deleted 7 characters in body Apr15 asked Express block matrix in terms of matrix basis Sep5 awarded Nice Answer Jul25 comment Result of Integrate depends on order of integration although the domain is rectangular @Jens,@MichaelE2: According to The Lebesgue-Stieltjes integral, p. 118, absolute convergence implies that the order does not matter (Fubini's theorem). Nintegrate over the absolute integrand yields Numerical integration converging too slowly[...]. As I increase the upper limit, the integral seems to increase with always diminishing rate, which indicates that it converges. I'm not very knowledgeable about the intricacies of integration, as I'm a physicist. Apparently, I need to learn more... Jul25 asked Result of Integrate depends on order of integration although the domain is rectangular Jul24 comment Mathematica 10 fails to calculate integral that Mathematica 9 can handle It is correct, thanks. I get three results of varying complexity, depending on the version of Mathematica, and v. 10 cannot solve this if I swap the order of the variables of integration. v.10 after swap and yours give the simplest results. Unfortunately, the simplicity of the result does not remain constant or increase as the version increases, and it is quite obvious that most built-in simplifications do not work for the result I quoted above. Is there a way to configure how Integrate calculates the result? Jul23 comment Mathematica 10 fails to calculate integral that Mathematica 9 can handle Please disregard my previous comment. Mathematica 10 can find the integral if I change the order of integration. Mathematica 9 cannot find it in this case after waiting for tens of minutes. Jul23 comment Mathematica 10 fails to calculate integral that Mathematica 9 can handle Now this is getting weird: in v. 10 I get 1/2 Mass (1/r1 + \[Pi]/(2 Rotation) - ArcTan[r1/Rotation]/Rotation + ( Rotation ArcTan[Rotation/r1])/r1^2), which is the correct result and is much more simple than that of v.9, even though I didn't use Simplify and nothing, that I'm aware of, changed meanwhile! Jul23 comment Mathematica 10 fails to calculate integral that Mathematica 9 can handle @MitchellKaplan I didn't; @Öskå probably edited my question and replaced \[Theta] with $\theta$ etc. Jul23 comment Mathematica 10 fails to calculate integral that Mathematica 9 can handle Now that I tried it without Simplify, Mathematica 10 takes twice as long as Mathematica 9 albeit without result. The problem is not that Simplify is time-constrained; it is that the integral cannot be calculated. Jul23 comment Mathematica 10 fails to calculate integral that Mathematica 9 can handle I didn't, because it takes far longer in Mathematica 10 than in Mathematica 9 for this to return, which seems to be a bug, too. Jul23 asked Mathematica 10 fails to calculate integral that Mathematica 9 can handle