DirichletBC

dirichletbc.jl

struct DirichletBC{T}
    l::T
    r::T
end

struct BoundaryPaddedArray{T,T2 <: AbstractVector{T}}
    l::T
    r::T
    u::T2
end

Base.:*(Q::DirichletBC,u) = BoundaryPaddedArray(Q.l,Q.r,u)
Base.length(Q::BoundaryPaddedArray) = length(Q.u) + 2
Base.lastindex(Q::BoundaryPaddedArray) = Base.length(Q)
function Base.getindex(Q::BoundaryPaddedArray,i)
    @show i
    if i == 1
        return Q.l
    elseif i == length(Q)
        return Q.r
    else
        return Q.u[i-1]
    end
end

x = range(-2π,stop=2π,length=100)[2:end-1]
u = @. (x-2π)*(x+2π)

Q = DirichletBC(0.0,0.0)

v = Q*u

v[1]
v[2]
v[end-1]
v[end]