# Error using delay\_fnn
**URL:** https://discourse.julialang.org/t/error-using-delay-fnn/132297
**Category:** Modelling & Simulations
**Tags:** dynamical-systems
**Created:** [September 11, 2025, 4:54pm UTC](https://discourse.julialang.org/t/error-using-delay-fnn/132297 "2025-09-11T16:54:17Z")
**Posts on this page:** 4
**Page:** 1
### Author:  [@dylanmcn](https://discourse.julialang.org/u/dylanmcn)
#### Post date: [September 11, 2025, 4:54pm UTC](https://discourse.julialang.org/t/error-using-delay-fnn/132297/1 "2025-09-11T16:54:17Z")
Hello,
I am trying to use the delay\_fnn function in the DynamicalSystems package and I keep getting the following error:
ERROR: MethodError: no method matching StateSpaceSet{2, Float64, SVector{2, Float64}, Nothing}(::Vector{SVector{2, Float64}})
The type `StateSpaceSet{2, Float64, SVector{2, Float64}, Nothing}` exists, but no method is defined for this combination of argument types when trying to construct it.
Here is the code:
'function lorenz96\_rule!(du, u, p, t)
F = p[1]; N = length(u)
# 3 edge cases
du[1] = (u[2] - u[N - 1]) \* u[N] - u[1] + F
du[2] = (u[3] - u[N]) \* u[1] - u[2] + F
du[N] = (u[1] - u[N - 2]) \* u[N - 1] - u[N] + F
# then the general case
for n in 3:(N - 1)
du[n] = (u[n + 1] - u[n - 2]) \* u[n - 1] - u[n] + F
end
return nothing # always `return nothing` for in-place form!
end
N = 6
u0 = range(0.1, 1; length = N)
p0 = [8.0]
lorenz96 = CoupledODEs(lorenz96\_rule!, u0, p0)
total\_time = 12.5
sampling\_time = 0.02
Y, t = trajectory(lorenz96, total\_time; Ttr = 2.2, Δt = sampling\_time)
z = Y[:, 1]
τ = estimate\_delay(z, “mi\_min”)
Ed = delay\_fnn(z, τ, 2:8)’
Thanks for any help. New to Julia (from Matlab) but familiar with attractor reconstruction.
---
### Author:  [@Datseris](https://discourse.julialang.org/u/Datseris)
#### Post date: [September 11, 2025, 8:24pm UTC](https://discourse.julialang.org/t/error-using-delay-fnn/132297/2 "2025-09-11T20:24:39Z")
sorry, this is because of StateSpaceSets.jl v2.5. I did a cool change there but it changed some internals. I thought it wouldn’t break anything downstream but it did! It should be fixed by the next time you update your packages.
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### Author:  [@Datseris](https://discourse.julialang.org/u/Datseris)
#### Post date: [September 11, 2025, 8:34pm UTC](https://discourse.julialang.org/t/error-using-delay-fnn/132297/3 "2025-09-11T20:34:37Z")
I just released a fix let me know if it works or not.
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### Author:  [@dylanmcn](https://discourse.julialang.org/u/dylanmcn)
#### Post date: [September 11, 2025, 9:41pm UTC](https://discourse.julialang.org/t/error-using-delay-fnn/132297/4 "2025-09-11T21:41:28Z")
It worked!! Thanks so much for the prompt reply and smooth solution.