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 Oct 25 comment Stochastic Schrödinger Equation Well start small. Do you know how to write the code for n=1? If not, your question is actually about solving SDEs in general. Oct 9 awarded Good Answer Sep 11 awarded Nice Answer Sep 1 comment Does Mathematica support Laguerre Polynomials of Matrix Argument? @belisarius nah I'm on holidays. Why don't you go ahead and do it? Aug 13 awarded Good Answer Jul 7 awarded Nice Answer Jun 5 comment NDSolve break condition @Ian excellent, up voted. Happy to serve as a guinea pig. May 17 awarded Good Answer May 13 awarded Enlightened May 13 awarded Nice Answer Apr 27 comment Finding adjacency matrix of a Mathematica's in-built graph? Dodecahedral is a symbol, not a graph. You want this: d = GraphData["DodecahedralGraph"]; AdjacencyMatrix[d], I think. Apr 8 awarded Nice Answer Feb 28 comment How to define a function something like f[u_[x_]] := x, but defining a function that takes as a second argument the derivative of the first is more involved. Jan 31 awarded Nice Answer Jan 31 comment Does Mathematica support Laguerre Polynomials of Matrix Argument? So operationally, you can think of MatrixFunction as taking a scalar function as the first arg, finding its series expansion, then using that to turn it into a matrix function and finally applying that to the second arg. If the second arg can eg be diagonalised via an orthogonal transformation, all you'd need to do do the transformation, apply a polynomial to the eigenvals and undo the transformation. Jan 31 comment Does Mathematica support Laguerre Polynomials of Matrix Argument? Oops you're right, LaguerreL is Listable so it just threads. OK, this does what you want I think: m = # + Transpose@# &@RandomReal[{-1, 1}, {10, 10}]; MatrixFunction[LaguerreL[3.2, #] &, m] (the idea is that MatrixFunction takes a scalar fn as the first arg, turns it into a matrix function and applies it to the second argument). Unless you actually do want a scalar as the output but then you need to explain how you want to get it. Jan 30 comment Does Mathematica support Laguerre Polynomials of Matrix Argument? it produces a 10 by 10 matrix of elements drawn from a uniform random distribution and then adds it to its transpose. I just wanted a symmetric matrix. Jan 30 comment Does Mathematica support Laguerre Polynomials of Matrix Argument? Apparently yes, eg m = # + Transpose@# &@RandomReal[{-1, 1}, {10, 10}]; LaguerreL[3.2, m] seems to work. In general you could also use MatrixFunction for this sort of thing. Jan 20 comment Why is (-1.)^2. a complex number @xslittlegrass I see. No idea then. Jan 20 comment Why is (-1.)^2. a complex number Look: Plot[{Re@#, Im@#} &@((-1)^x), {x, 1.5, 2.5}]