`y=f(x)` where `f` creates randvars and `x` is range (i.e. should be array)

[zenna]

nx = 10
xcoarse = 1:nx
f(x) = sin(2pi/(nx-1) * (x-1)) + uniform(0,1)
ycoarse = f(xcoarse)

Errors with

ERROR: LoadError: MethodError: `+` has no method matching +(::Array{Float64,1}, ::Sigma.PlusRandVar{Float64,Float64,Int64})
Closest candidates are:
  +(::Any, ::Any, !Matched::Any)
  +(::Any, ::Any, !Matched::Any, !Matched::Any...)
  +{T1<:Real,T2<:Real}(!Matched::T1<:Real, ::Sigma.SymbolicRandVar{T2<:Real})
  ...
 in f at /home/zenna/repos/Sigma.jl/examples/splineinterpolation.jl:6
while loading /home/zenna/repos/Sigma.jl/examples/splineinterpolation.jl, in expression starting on line 7