Pleiades Work-Precision Diagrams

Chris Rackauckas
using OrdinaryDiffEq, ODE, ODEInterfaceDiffEq, LSODA, Sundials, DiffEqDevTools

f = (du,u,p,t) -> begin
  @inbounds begin
  x = view(u,1:7)   # x
  y = view(u,8:14)  # y
  v = view(u,15:21) # x′
  w = view(u,22:28) # y′
  du[1:7] .= v
  du[8:14].= w
  for i in 15:28
    du[i] = zero(u[1])
  end
  for i=1:7,j=1:7
    if i != j
      r = ((x[i]-x[j])^2 + (y[i] - y[j])^2)^(3/2)
      du[14+i] += j*(x[j] - x[i])/r
      du[21+i] += j*(y[j] - y[i])/r
    end
  end
  end
end

prob = ODEProblem(f,[3.0,3.0,-1.0,-3.0,2.0,-2.0,2.0,3.0,-3.0,2.0,0,0,-4.0,4.0,0,0,0,0,0,1.75,-1.5,0,0,0,-1.25,1,0,0],(0.0,3.0))

abstols = 1.0 ./ 10.0 .^ (6:9)
reltols = 1.0 ./ 10.0 .^ (3:6);

using Plots; gr()
Plots.GRBackend()
sol = solve(prob,Vern8(),abstol=1/10^12,reltol=1/10^10,maxiters=1000000)
test_sol = TestSolution(sol);
plot(sol)