Plotting differential equations solutions with varying color

Specific Domains Visualization
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1

When plotting DifferentialEquations solutions, the plotdensity keyword does not seem to work together with line_z. See code below where data interpolation within Plots does not take place, when we color the solution by the simulation time array (line_z=sol0.t):

using DifferentialEquations, ParameterizedFunctions, Plots
lorenz = @ode_def begin           
    dx = σ*(y - x);  dy = x*(ρ - z) - y; dz = x*y - β*z
 end σ ρ β
u0=[1.,1.,1.]; tspan=(0.,60.); p=[10.,28.,8/3];
prob = ODEProblem(lorenz, u0, tspan, p) 
sol0 = solve(prob, reltol=1e-9) 
# plot(sol0, vars = (1, 2, 3))  # display interpolation is on but line_z not working with this syntax
plot((sol0[1,:],sol0[2,:],sol0[3,:]), line_z=sol0.t, plotdensity=10_000, color=:redsblues)

ODE_line_varying_color

Is this possible to do using Plots?

2

This is not using the recipe since you explicitly told it what arrays you wanted to plot.

If you did line_z = sol0.t, well, that isn’t going to be the right length array since it needs to match the interpolation length.

The workaround is to manually interpolate and plot. But open an issue. What we will need to handle is line_z = 0 and then it would need to build the array in the recipe itself.

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