how to print out the state vector inside the "eom" function?

[Igor]

Trying to print out some state vector components for debugging. After @printf, getting Errors like

Stacktrace:
 [1] fix_dec(::ForwardDiff.Dual{ForwardDiff.Tag{DynamicalSystemsBase.var"#13#20"{cnh_tpt.cnhLoopParams,Float64,typeof(cnh_tpt.hcLoop)},Float64},Float64,4}, ::Int64, ::Array{UInt8,1}) at /buildworker/worker/package_linux64/build/usr/share/julia/stdlib/v1.5/Printf/src/Printf.jl:992 (repeats 79984 times)

how to convert state vector components to smth. like Float64?

function hcLoop(sv::SVector{4}, params::cnhLoopParams, t)
	x = sv[1]
        @printf "x = %.3f \n" x

[George Datseris]

using DynamicalSystems

function f(u, p, t)
    @show u
    return u
end

ds = ContinuousDynamicalSystem(f, [0.1, 0.1], nothing)

tr = trajectory(ds, 1.0)

this works for me:

julia> 
ForwardDiff.Dual{ForwardDiff.Tag{DynamicalSystemsBase.var"#13#20"{Nothing,Float64,typeof(f)},Float64},Float64,2}[Dual{ForwardDiff.Tag{DynamicalSystemsBase.var"#13#20"{Nothing,Float64,typeof(f)},Float64}}(0.1,1.0,0.0), Dual{ForwardDiff.Tag{DynamicalSystemsBase.var"#13#20"{Nothing,Float64,typeof(f)},Float64}}(0.1,0.0,1.0)]
u = [0.1, 0.1]
[0.1, 0.1]
u = [0.100161, 0.100161]
u = [0.10032754012385535, 0.10032754012385535]
u = [0.1009040495557949, 0.1009040495557949]
u = [0.10098482453597712, 0.10098482453597712]
u = [0.10100499687894175, 0.10100499687894175]
u = [0.10100501670841681, 0.10100501670841681]
u = [0.1020601322646853, 0.1020601322646853]
u = [0.10317098209099486, 0.10317098209099486]
u = [0.10708086871070818, 0.10708086871070818]
u = [0.1076402264448548, 0.1076402264448548]
u = [0.10778025312641576, 0.10778025312641576]
u = [0.10777580914103836, 0.10777580914103836]
u = [0.10975325970738052, 0.10975325970738052]
u = [0.11186772348627237, 0.11186772348627237]
u = [0.11943098742941127, 0.11943098742941127]
u = [0.1205375994227601, 0.1205375994227601]
u = [0.12081501594254732, 0.12081501594254732]
u = [0.12078532662732924, 0.12078532662732924]
u = [0.12339659287623253, 0.12339659287623253]
u = [0.1262065875037564, 0.1262065875037564]
u = [0.13632819106555924, 0.13632819106555924]
u = [0.13782422463429936, 0.13782422463429936]
u = [0.13819941761258156, 0.13819941761258156]
u = [0.13814374015461184, 0.13814374015461184]
u = [0.14178528671719673, 0.14178528671719673]
u = [0.14573994879888746, 0.14573994879888746]
u = [0.16013402260555076, 0.16013402260555076]
u = [0.16229459490701853, 0.16229459490701853]
u = [0.16283667594624307, 0.16283667594624307]
u = [0.16271902402664656, 0.16271902402664656]
u = [0.16754618121244047, 0.16754618121244047]
u = [0.17282164141303924, 0.17282164141303924]
u = [0.1921671357693794, 0.1921671357693794]
u = [0.19510351167562898, 0.19510351167562898]
u = [0.1958403742297839, 0.1958403742297839]
u = [0.19564138373304862, 0.19564138373304862]
u = [0.20208753453305506, 0.20208753453305506]
u = [0.20917644618016681, 0.20917644618016681]
u = [0.23536971285473424, 0.23536971285473424]
u = [0.23939093583000065, 0.23939093583000065]
u = [0.24040013435246885, 0.24040013435246885]
u = [0.24007090158850591, 0.24007090158850591]
u = [0.24854911772014557, 0.24854911772014557]
u = [0.2579145268366372, 0.2579145268366372]
u = [0.29271204922797783, 0.29271204922797783]
u = [0.29809895045649226, 0.29809895045649226]
u = [0.2994509255894264, 0.2994509255894264]
u = [0.2989526001553013, 0.2989526001553013]

[George Datseris]

Anything related to ForwardDiff comes because you have not written the Jacobian yourself, if you get system specific errors try writing down the Jacobian.

[Igor]

Thanks for the answer! @show works.

Jacobian will not help me, while trying to investigate stupid issues like wrong units/models.
If there could be a way to convert this "ForwardDiff" into Float64, this would be very helpful. Need some way to export somehow intermediate results for debugging.

[George Datseris]

just use print instead of this weird macro and all should be okay. print and show, the Julia functions, are defined for everything by default. @printf probably only for Real numbers.

[Igor]

Thanks!