Hello guys. I’m having trouble adapting a Matlab code that resolves a second-order ODE to the Julia equivalent.
This is the code in Matlab. It plots a graph with 3 curves:
syms y(x); dy = diff(y); edo = diff(y,x,2) == -0.1 * dy - 0.8 * y; Bound_1 = y(0) == 5e-3; Bound_2 = dy(0) == 0; conds = [Bound_1 Bound_2]; t = [0, 30]; ySol(x) = dsolve(edo, conds); figure(1) fplot(ySol, t) hold on fplot(diff(ySol), t) fplot(diff(ySol,2), t) hold off
This is my equivalent Julia version. However, the resulting graph has only two curves.
f2(du, u, p, t) = -0.1du - 0.8u u₀ = 5e-3 du₀ = 0.0 t = (0.0, 30.0) prob = SecondOrderODEProblem(f2, du₀, u₀, t) sol = solve(prob) plot(sol)
How do I make the
u'' curve appear in the graph generated by the julia?