VectorFun

[goretkin]

I'm trying to construct a vector-valued Fun as follows, but it doesn't seem to be a proper Fun. (It seems to work with FFun, though)

julia> y0 = Fun(x->[1.0, 0.0])
Fun{VectorDomainSpace{2,UltrasphericalSpace{0},Float64},Float64}([1.0],VectorDomainSpace{2,UltrasphericalSpace{0},Float64}(UltrasphericalSpace{0}(Interval{Float64}(-1.0,1.0))))

julia> y0[1.0]
ERROR: BoundsError()
 in clenshaw at /Users/goretkin/.julia/v0.3/ApproxFun/src/LinearAlgebra/clenshaw.jl:28
 in evaluate at /Users/goretkin/.julia/v0.3/ApproxFun/src/Multivariate/VectorFun.jl:69
 in getindex at /Users/goretkin/.julia/v0.3/ApproxFun/src/Fun/Fun.jl:69

[goretkin]

weird. y = Fun(x->[0.0, 1.0] ) doesn't cause the same error

[goretkin]

I understand the reason behind using [] indexing on Funs, to emphasize that these are infinite dimensional vectors, but vectors nonetheless. I think, though, it might be interesting to consider using () to index the Fun variable, and [] to access elements of multi-dimensional valued Funs (like vector valued Funs, not multivariate Funs)

[dlfivefifty]

Yes I agree. The real reason for overriding [] is it wasn’t impossible to override() in 0.3. But it should be in 0.4.

In the meantime, you vec(f) will convert it vector-valued Fun to a vector of scalar-valued funs, so you can do e.g. vec(f)[1][.1]

Sheehan

On 2 Dec 2014, at 10:48 am, Gustavo Goretkin notifications@github.com wrote:

I understand the reason behind using [] indexing on Funs, to emphasize that these are infinite dimensional vectors, but vectors nonetheless. I think, though, it might be interesting to consider using () to index the Fun variable, and [] to access elements of multi-dimensional valued Funs (like vector valued Funs, not multivariate Funs)

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Reply to this email directly or view it on GitHub #51 (comment).

[goretkin]

Good to know that!

[goretkin]

Here is a different error when trying to construct a vector-valued fun

julia> Fun(x->Float64[0.0], 50)
ERROR: `plan_r2r` has no method matching plan_r2r(::Array{Array{Float64,1},1}, ::Int32, ::UnitRange{Int64}, ::Uint32, ::Float64)
 in chebyshevtransform at /Users/goretkin/.julia/v0.3/ApproxFun/src/LinearAlgebra/chebyshevtransform.jl:27
 in transform at /Users/goretkin/.julia/v0.3/ApproxFun/src/Spaces/Ultraspherical/ChebyshevSpace.jl:22
 in Fun at /Users/goretkin/.julia/v0.3/ApproxFun/src/Fun/constructors.jl:10
 in Fun at /Users/goretkin/.julia/v0.3/ApproxFun/src/Fun/constructors.jl:26

[goretkin]

Sorry for the rapid-fire. Is there a way to convert from an Array of scalar-valued Funs to a Vector Fun? the opposite of vec()

[dlfivefifty]

devec()

Sent from my iPhone

On 2 Dec 2014, at 11:37 am, Gustavo Goretkin notifications@github.com wrote:

Sorry for the rapid-fire. Is there a way to convert from an Array of scalar-valued Funs to a Vector Fun? the opposite of vec()

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Reply to this email directly or view it on GitHub.