Tube plots?

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7

Thanks @rafael.guerra, that looks like just what I want, and the prospect of using AD is nice too. Unfortunately when I run your code I get a method error for svd!, am I missing a package? I’m on v1.6.2 and the full stacktrace is

ERROR: MethodError: no method matching svd!(::Vector{Float64}; full=true, alg=LinearAlgebra.DivideAndConquer())
Closest candidates are:
  svd!(::LinearAlgebra.AbstractTriangular; kwargs...) at C:\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.6\LinearAlgebra\src\triangular.jl:2212
  svd!(::StridedMatrix{T}; full, alg) where T<:Union{Float32, Float64, ComplexF32, ComplexF64} at C:\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.6\LinearAlgebra\src\svd.jl:92
  svd!(::StridedMatrix{T}, ::StridedMatrix{T}) where T<:Union{Float32, Float64, ComplexF32, ComplexF64} at C:\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.6\LinearAlgebra\src\svd.jl:361 got unsupported keyword arguments "full", "alg"
  ...
Stacktrace:
  [1] svd(A::Vector{Float64}; full::Bool, alg::LinearAlgebra.DivideAndConquer)
    @ LinearAlgebra C:\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.6\LinearAlgebra\src\svd.jl:157  
  [2] svd(A::Adjoint{Float64, Vector{Float64}}; full::Bool, alg::LinearAlgebra.DivideAndConquer)
    @ LinearAlgebra C:\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.6\LinearAlgebra\src\svd.jl:166  
  [3] #nullspace#30
    @ C:\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.6\LinearAlgebra\src\dense.jl:1446 [inlined]   
  [4] nullspace(A::Adjoint{Float64, Vector{Float64}})
    @ LinearAlgebra C:\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.6\LinearAlgebra\src\dense.jl:1444
  [5] C(s::Float64, u::Float64)
    @ Main .\REPL[9]:2
  [6] _broadcast_getindex_evalf
    @ .\broadcast.jl:648 [inlined]
  [7] _broadcast_getindex
    @ .\broadcast.jl:621 [inlined]
  [8] getindex
    @ .\broadcast.jl:575 [inlined]
  [9] copy
    @ .\broadcast.jl:922 [inlined]
 [10] materialize(bc::Base.Broadcast.Broadcasted{Base.Broadcast.DefaultArrayStyle{2}, Nothing, typeof(C), Tuple{LinRange{Float64}, Adjoint{Float64, LinRange{Float64}}}})
    @ Base.Broadcast .\broadcast.jl:883
 [11] (::var"#29#31")(i::Int64)
    @ Main .\none:0
 [12] iterate
    @ .\generator.jl:47 [inlined]
 [13] collect(itr::Base.Generator{UnitRange{Int64}, var"#29#31"})
    @ Base .\array.jl:678
 [14] top-level scope
    @ REPL[12]:1
```