sosiristseng / jl-things Goto Github PK

using LabelledArrays
using DifferentialEquations
using SimpleUnPack
using Plots

## SIR model, in-place form: f!(du, u, p ,t)
function sir!(D, u, p ,t)
	@unpack s, i, r = u
	@unpack β, γ = p
	v1 = β * s * i
	v2 = γ * i

    D.s = -v1
    D.i = v1 - v2
    D.r = v2
	return nothing
end

# Parameters, initial conditions, and time span of the SIR model
p = LVector(β = 1.0, γ = 0.3)
u0 = LVector(s=0.99, i=0.01, r=0.00)
tspan = (0.0, 20.0)

prob = ODEProblem(sir!, u0, tspan, p) ## Define the problem
sol = solve(prob) ## Solve the problem
sol(0.:1.:20.)[:s] ## Error
plot(sol, idxs=(:s, :i)) ## Works?!

# Let's fix it
f = ODEFunction(sir!, syms=keys(u0), paramsyms=keys(p))
prob = ODEProblem(f, u0, tspan, p) ## Define the problem
sol = solve(prob) ## Solve the problem
sol(0.:1.:20.)[:s] ## Works

plot(sol, idxs=(:s, :i)) ## Works

Agents.abmvideo(
    "flocking.mp4", model, agent_step!;
    am = bird_marker,
    framerate = 20, frames = 200,
    figure = (size = (600, 600),),
    title = "Flocking"
)