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Some time ago I asked the following question on how to calculate the radial distribution function. I have here an add-on question, but before asking it I try to summarize and visualize my problem. As input I have an image where particles are seen as bright dots: After determining the positions of all particles, byRead more

I have a simple system of ODEs: Clear[Omega, r1, r2, X, Y, mu, Vx, Vy] Omega = (0.5) ((1 – mu) r1^2 + mu r2^2) + mu/r2 + (1 – mu)/r1; r1 = ((X[t] – mu)^2 + Y[t]^2)^(0.5); r2 = ((X[t] + 1 – mu)^2 + Y[t]^2)^(0.5); VxEquation = Simplify[D[Vx[t], t] – 2.0 Vy[t] –Read more

I would like to construct a rectangular matrix which doesn’t have a decomposition into a product of a sparse and a small matrices. It is easy to see that a random matrix doesn’t have such a representation, but I’d like to find an explicit example. More precisely, I want to find an explicit matrix $Read more