--- a/diffOp.jl	Mon Dec 17 16:30:39 2018 +0100
+++ b/diffOp.jl	Mon Dec 17 16:35:08 2018 +0100
@@ -16,7 +16,7 @@
     error("not implemented")
 end
 
-function interface(Du::DiffOp, Dv::DiffOp, b::BoundaryID; type)
+function interface(Du::DiffOp, Dv::DiffOp, b::grid.BoundaryId; type)
     error("not implemented")
 end
 
@@ -29,19 +29,23 @@
 end
 
 # u = L*v
-function apply(L::Laplace1D, u::AbstractVector, v::AbstractVector)::AbstractVector
+function apply(L::Laplace1D, u::AbstractVector, v::AbstractVector)
     N = closureSize(L.op)
     M = length(v)
 
+    h = scaling(L.grid)
+
     for i ∈ 1:N
-        u[i] = apply(L.op.closureStencils[i], v, i)
+        u[i] = apply(L.op.closureStencils[i], v, i)/h^2
     end
 
     for i ∈ N+1:M-N
-        u[i] = apply(L.op.innerStencil, i);
+        u[i] = apply(L.op.innerStencil, i)/h^2
     end
 
     for i ∈ M:-1:M-N+1
-        u[i] = apply(flip(L.op.closureStencils[M-i+1]), v, i)
+        u[i] = apply(flip(L.op.closureStencils[M-i+1]), v, i)/h^2
     end
+
+    return nothing
 end

--- a/grid.jl	Mon Dec 17 16:30:39 2018 +0100
+++ b/grid.jl	Mon Dec 17 16:35:08 2018 +0100
@@ -1,1 +1,54 @@
-abstract type BoundaryID end
+module grid
+
+abstract type Grid end
+
+function numberOfDimensions(grid::Grid)
+    error("Not yet implemented")
+end
+
+function numberOfPoints(grid::Grid)
+    error("Not yet implemented")
+end
+
+function points(grid::Grid)
+    error("Not yet implemented")
+end
+
+abstract type BoundaryId end
+
+# Move to seperate file.
+struct EquidistantGrid <: Grid
+    nPointsPerDim::Vector{Int}
+    limits::Vector{Pair{Real, Real}}
+    function EquidistantGrid(nPointsPerDim, lims)
+        @assert length(lims) == length(nPointsPerDim)
+        return new(nPointsPerDim, lims)
+    end
+end
+
+function numberOfDimensions(grid::EquidistantGrid)
+    return length(grid.nPointsPerDim)
+end
+
+function numberOfPoints(grid::EquidistantGrid)
+    numberOfPoints = grid.nPointsPerDim[1];
+    for i = 2:length(grid.nPointsPerDim);
+        numberOfPoints = numberOfPoints*grid.nPointsPerDim[i]
+    end
+    return numberOfPoints
+end
+
+function points(grid::EquidistantGrid)
+    points = Vector{Real}(undef, numberOfPoints(grid))
+    for i = 1:numberOfDimensions(grid)
+        lims = limitsForDimension(grid,i)
+        points = range(lims.first, stop=lims.second, length=grid.nPointsPerDim[i])
+    end
+    return points
+end
+
+function limitsForDimension(grid::EquidistantGrid, dim::Int)
+    return grid.limits[dim]
+end
+
+end