developing new tests

basic_example.jl

@@ -0,0 +1,61 @@
+using NetworkDynamics
+using LightGraphs
+using LinearAlgebra
+using SparseArrays
+using DifferentialEquations
+using Plots
+
+struct SolAnalytic
+    L
+end
+function (sa::SolAnalytic)(x0, p, t)
+    exp(- t * sa.L) * x0
+end
+
+g = barabasi_albert(10,5)
+
+L = laplacian_matrix(g)
+
+sol_analytic = SolAnalytic(Symmetric(Array(L)))
+
+diff_network_L = ODEFunction((dx, x, p, t) -> dx .= - L * x, analytic=sol_analytic)
+
+x0 = rand(10)
+
+prob_L = ODEProblem(diff_network_L,x0,(0.,5.))
+sol_L = solve(prob_L)
+
+println(sol_L.errors)
+
+plot(sol_L)
+
+sol_ana = zeros(length(sol_L.t), length(x0))
+for i in 1:length(sol_L.t)
+    sol_ana[i, :] .= sol_analytic(x0, nothing, sol_L.t[i])
+end
+plot(sol_L.t, sol_ana)
+
+#Now for NetworkDynamics
+
+diffusion_edge! = (e,v_s,v_d,p,t) -> @. e = v_s - v_d
+
+function diffusion_vertex!(dv, v, e_s, e_d, p, t)
+    dv .= edge_sum(e_s, e_d) # Oriented sum of the incoming and outgoing edges
+end
+
+odevertex = ODEVertex(f! = diffusion_vertex!,dim = 1)
+staticedge = StaticEdge(f! = diffusion_edge!, dim = 1)
+odeedge = ODEEdge(staticedge) # We promote the static edge to an ODEEdge artifically
+
+vertex_list = [odevertex for v in vertices(g)]
+edge_list = [staticedge for e in edges(g)]
+
+diff_network_st = network_dynamics(vertex_list,edge_list,g)
+
+x0 = rand(10)
+
+prob_st = ODEProblem(diff_network_st,x0,(0.,5.))
+
+sol_st = solve(prob_st)
+
+plot(sol_st)

src/Utilities.jl

@@ -4,6 +4,30 @@ using NLsolve
 using DifferentialEquations
 using LinearAlgebra
 
+export edge_sum!, edge_sum
+
+function edge_sum!(e_sum, e_s, e_d)
+    for e in e_s
+        e_sum .-= e
+    end
+    for e in e_d
+        e_sum .+= e
+    end
+    nothing
+end
+
+function edge_sum(e_s, e_d)
+    e_sum = similar(e_s)
+    e_sum .= 0.
+    for e in e_s
+        e_sum .-= e
+    end
+    for e in e_d
+        e_sum .+= e
+    end
+    e_sum
+end
+
 export RootRhs
 
 struct RootRhs