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Timeline for Express MeijerG as integral

Current License: CC BY-SA 4.0

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Jun 14, 2021 at 14:56 history bounty awarded granular_bastard
Jun 14, 2021 at 14:56 vote accept granular_bastard
Jun 13, 2021 at 12:49 comment added yarchik @granularbastard In the function MeijerGIntegral the result of Mellin transform s typically contains a product of several Gamma functions. Next, I split it into a product of two terms sA and sB, where sA necessarily contains Gamma. This splitting is not unique. If you would like to have a different result, you need to split in a different way making sure that for both sA and sB the InverseMellinTransform exists.
Jun 13, 2021 at 12:41 comment added granular_bastard The given routine works for the examples of the OP, but for other examples it returns a result that contains another shorter Meijer G-function. How to deal in these cases? Example: MeijerGIntegral[ MeijerG[{{}, {}}, {{0, 1/2, 1, 3/2, 2, 5/2, 3}, {}}, x], x, t] Result: Exp[-Sqrt[t]] Sqrt[Pi]/t MeijerG[{{},{}},{{1,3/2,2,5/2,3},{}},4x/t]
Jun 12, 2021 at 17:56 history edited yarchik CC BY-SA 4.0
explanation is added.
Jun 12, 2021 at 17:46 comment added yarchik @mikado Thank you! In fact I am choosing among a smaller number of possibilities for the given examples. The Mellin transform will typically be given by a product of several Gamma functions. I choose on of them for the inverse Mellin and hope that the inverse Mellin can be done for the rest. There is no guarantee. In principle, one should try all possibilities and select the simplest answer. I will add a couple of sentences into my post.
Jun 12, 2021 at 14:48 comment added mikado This is really good. It would be nice to have some explanation of how it works. I think you are choosing arbitrarily 1 of 6? possible answers. It would be interesting to see all of them (we could perhaps choose the simplest).
Jun 12, 2021 at 13:10 history answered yarchik CC BY-SA 4.0