fixed L2P1 element and added test

Author: chmerdon

examples/Example281_DiscontinuousPlot.jl

@@ -61,9 +61,11 @@ function main(; broken = false, nrefs = 3, abs = false, Plotter = nothing)
     nodevals4nodes2 = nodevalues(FEFunction[1], Identity; abs = abs, regions = [2], nodes = subnodes2)
 
 	## plot
-	p = GridVisualizer(; Plotter = Plotter, layout = (2, 2), clear = true, resolution = (1000, 500))
-    gridplot!(p[1,1], xgrid)
-	scalarplot!(p[1, 2], [subgrid1, subgrid2], xgrid, [view(nodevals4nodes1,:), view(nodevals4nodes2,:)], cellwise = false, levels = 11, title = "u")
+    if Plotter !== nothing
+	    p = GridVisualizer(; Plotter = Plotter, layout = (2, 2), clear = true, resolution = (1000, 500))
+        gridplot!(p[1,1], xgrid)
+	    scalarplot!(p[1, 2], [subgrid1, subgrid2], xgrid, [view(nodevals4nodes1,:), view(nodevals4nodes2,:)], cellwise = false, levels = 11, title = "u")
+    end
 
     return p
 end

src/fedefs/l2_p1.jl

@@ -31,6 +31,7 @@ get_dofmap_pattern(FEType::Type{<:L2P1}, ::Type{CellDofs}, EG::Type{<:AbstractEl
 
 isdefined(FEType::Type{<:L2P1}, ::Type{<:AbstractElementGeometry}) = true
 
+init_interpolator!(FES::FESpace{Tv, Ti, FEType, APT}, ::Type{AT_NODES}) where {Tv, Ti, FEType <: L2P1, APT} = NodalInterpolator(FES)
 function ExtendableGrids.interpolate!(Target, FE::FESpace{Tv, Ti, FEType, APT}, ::Type{AT_NODES}, exact_function!; items = [], kwargs...) where {Tv, Ti, FEType <: L2P1, APT}
     return get_interpolator(FE, AT_NODES).evaluate!(Target, exact_function!, items; kwargs...)
 end
@@ -50,7 +51,7 @@ end
 function ExtendableGrids.interpolate!(Target, FE::FESpace{Tv, Ti, FEType, APT}, ::Type{ON_CELLS}, exact_function!; items = [], kwargs...) where {Tv, Ti, FEType <: L2P1, APT}
     return if FE.broken == true
         # broken interpolation
-        interpolate!(Target, FE, AT_NODES, exact_function!; items = items, kwargs...)
+        get_interpolator(FE, AT_NODES).evaluate!(Target, exact_function!, items; kwargs...)
     else
         # delegate cell nodes to node interpolation
         subitems = slice(FE.dofgrid[CellNodes], items)

src/interpolators.jl

@@ -34,7 +34,6 @@ function NodalInterpolator(
     kwargs...) where {T}
     FEType = eltype(FES)
     ncomponents = get_ncomponents(FEType)
-    offset4component = 0:component_offset:(ncomponents * component_offset)
     xCoordinates = grid[Coordinates]
     xCellRegions = grid[CellRegions]
     result = zeros(T, ncomponents)
@@ -59,7 +58,7 @@ function NodalInterpolator(
                 for n in 1:nnodes_on_cell
                     j = xCellNodes[n, cell]
                     QP.x .= view(xCoordinates, :, j)
-                    exact_function(result, QP)
+                    exact_function!(result, QP)
                     for k in 1:ncomponents
                         target[xCellDofs[1, cell] + n - 1 + (k - 1) * nnodes_on_cell] = result[k]
                     end
@@ -69,6 +68,7 @@ function NodalInterpolator(
         return NodalInterpolator(evaluate_broken!)
     else
         ## FE space is continuous in node, so only one evaluation is required
+        offset4component = 0:component_offset:(ncomponents * component_offset)
         nnodes = num_nodes(grid)
         xNodeCells = atranspose(grid[CellNodes])
         function evaluate!(target, exact_function!, items; time = 0, params = [], kwargs...)

test/test_interpolators.jl

@@ -25,6 +25,7 @@ function run_interpolator_tests()
         HDIVRTk{2, 3},
         HDIVRTk{2, 4},
         L2P0{2},
+        L2P1{2},
         H1P1{2},
         H1Q1{2},
         H1CR{2},
@@ -39,7 +40,7 @@ function run_interpolator_tests()
         H1Pk{2, 2, 4},
         H1Pk{2, 2, 5},
     ]
-    ExpectedOrders2D = [0, 1, 0, 0, 1, 1, 1, 2, 2, 3, 4, 0, 1, 1, 1, 1, 1, 1, 2, 2, 2, 3, 3, 4, 5]
+    ExpectedOrders2D = [0, 1, 0, 0, 1, 1, 1, 2, 2, 3, 4, 0, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 3, 3, 4, 5]
 
     TestCatalog3D = [
         HCURLN0{3},