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The phase portrait gives you $y'$ as a function of $y$ in multiple pieces (all those intervals where the former is actually a unique function). In each such piece, you can in principle find the functional form $dy/dt = y' = g(y)$ by inspection. Next, how to get the time? Use $$t-t_i = \int \frac{dy}{g(y)} $$ which is then solvable for $y(t-t_i)$ in ...


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I have previously used the following two helper functions to generate the format of covariance and correlation matrices: covariancematrix[n_] := Table[ σ[i] σ[j] ρ[i, j]^(1 - KroneckerDelta[i, j]), {i, 1, n, 1}, {j, 1, n, 1} ] /. {ρ[i_, j_] :> ρ[j, i] /; i > j} correlationmatrix[n_] := Table[ σ[i] σ[j] ρ[i, j]^(1 - KroneckerDelta[i, ...



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