From 7e4cfcde5284d343e678a3fa03818391c40efab5 Mon Sep 17 00:00:00 2001 From: Fredrik Ekre Date: Mon, 11 Oct 2021 16:06:43 +0200 Subject: [PATCH] Support matrix input for L2 projection. --- src/L2_projection.jl | 46 +++++++++++++++++++++++++------------- test/test_l2_projection.jl | 30 +++++++++++++++++++------ 2 files changed, 54 insertions(+), 22 deletions(-) diff --git a/src/L2_projection.jl b/src/L2_projection.jl index d7948e289d..4dc392972a 100644 --- a/src/L2_projection.jl +++ b/src/L2_projection.jl @@ -85,7 +85,7 @@ function L2Projector( _, vertex_dict, _, _ = __close!(dh) M = _assemble_L2_matrix(fe_values_mass, set, dh) # the "mass" matrix - M_cholesky = cholesky(M) # TODO maybe have a lazy eval instead of precomputing? / JB + M_cholesky = cholesky(M) # For deprecated API fe_values = qr_rhs === nothing ? nothing : @@ -153,7 +153,7 @@ end """ - project(proj::L2Projector, vals::Vector{Vector{T}}}, qr_rhs::QuadratureRule; project_to_nodes=true) + project(proj::L2Projector, vals, qr_rhs::QuadratureRule; project_to_nodes=true) Makes a L2 projection of data `vals` to the nodes of the grid using the projector `proj` (see [`L2Projector`](@ref)). @@ -167,7 +167,9 @@ where ``f`` is the data to project, i.e. `vals`. The data `vals` should be a vector, with length corresponding to number of elements, of vectors, with length corresponding to number of quadrature points per element, matching the number of points in `qr_rhs`. -Example scalar input data: +Alternatively, `vals` can be a matrix, with number of columns corresponding to number of elements, +and number of rows corresponding to number of points in `qr_rhs`. +Example (scalar) input data: ```julia vals = [ [0.44, 0.98, 0.32], # data for quadrature point 1, 2, 3 of element 1 @@ -175,6 +177,14 @@ vals = [ # ... ] ``` +or equivalent in matrix form: +```julia +vals = [ + 0.44 0.29 # ... + 0.98 0.48 # ... + 0.32 0.55 # ... +] +``` Supported data types to project are `Number`s and `AbstractTensor`s. If the parameter `project_to_nodes` is `true`, then the projection returns the values in the order of the mesh nodes @@ -182,9 +192,9 @@ If the parameter `project_to_nodes` is `true`, then the projection returns the v field over the domain, which is useful if one wants to interpolate the projected values. """ function project(proj::L2Projector, - vars::Vector{Vector{T}}, + vars::AbstractVector{<:AbstractVector{T}}, qr_rhs::Union{QuadratureRule,Nothing}=nothing; - project_to_nodes::Bool=true) where T <: Union{Number, AbstractTensor} + project_to_nodes::Bool=true) where {T} # For using the deprecated API fe_values = qr_rhs === nothing ? @@ -192,26 +202,29 @@ function project(proj::L2Projector, CellScalarValues(qr_rhs, proj.func_ip, proj.geom_ip) M = T <: AbstractTensor ? length(vars[1][1].data) : 1 - make_T(vals) = T <: AbstractTensor ? T(Tuple(vals)) : vals[1] - projected_vals = _project(vars, proj, fe_values, M) + projected_vals = _project(vars, proj, fe_values, M, T)::Vector{T} if project_to_nodes # NOTE we may have more projected values than verticies in the mesh => not all values are returned nnodes = getnnodes(proj.dh.grid) - reordered_vals = fill(NaN, nnodes, size(projected_vals, 2)) + reordered_vals = fill(convert(T, NaN * zero(T)), nnodes) for node = 1:nnodes - if haskey(proj.node2dof_map, node) - reordered_vals[node, :] = projected_vals[proj.node2dof_map[node], :] + if (k = get(proj.node2dof_map, node, nothing); k !== nothing) + @assert length(k) == 1 + reordered_vals[node] = projected_vals[k[1]] end end - return T[make_T(reordered_vals[i,:]) for i=1:size(reordered_vals, 1)] + return reordered_vals else - # convert back to the original tensor type - return T[make_T(projected_vals[i,:]) for i=1:size(projected_vals, 1)] + return projected_vals end end +function project(p::L2Projector, vars::AbstractMatrix, qr_rhs::QuadratureRule; project_to_nodes=true) + # TODO: Random access into vars is required for now, hence the collect + return project(p, collect(eachcol(vars)), qr_rhs; project_to_nodes=project_to_nodes) +end -function _project(vars, proj::L2Projector, fe_values::Values, M::Integer) +function _project(vars, proj::L2Projector, fe_values::Values, M::Integer, ::Type{T}) where {T} # Assemble the multi-column rhs, f = ∭( v ⋅ x̂ )dΩ # The number of columns corresponds to the length of the data-tuple in the tensor x̂. @@ -251,6 +264,9 @@ function _project(vars, proj::L2Projector, fe_values::Values, M::Integer) end # solve for the projected nodal values - return proj.M_cholesky \ f + projected_vals = proj.M_cholesky \ f + # Recast to original input type + make_T(vals) = T <: AbstractTensor ? T(Tuple(vals)) : vals[1] + return T[make_T(x) for x in eachrow(projected_vals)] end diff --git a/test/test_l2_projection.jl b/test/test_l2_projection.jl index f6e665b043..6121955c10 100644 --- a/test/test_l2_projection.jl +++ b/test/test_l2_projection.jl @@ -39,14 +39,16 @@ function test_projection(order, refshape) # Now recover the nodal values using a L2 projection. proj = L2Projector(ip, grid; geom_ip=ip_geom) point_vars = project(proj, qp_values, qr) + qp_values_matrix = reduce(hcat, qp_values) + point_vars_2 = project(proj, qp_values_matrix, qr) ## Old API with fe values as first arg proj2 = @test_deprecated L2Projector(cv, ip, grid) - point_vars_2 = @test_deprecated project(qp_values, proj2) + point_vars_3 = @test_deprecated project(qp_values, proj2) ## Old API with qr as first arg proj3 = @test_deprecated L2Projector(qr, ip, grid) - point_vars_3 = @test_deprecated project(qp_values, proj3) + point_vars_4 = @test_deprecated project(qp_values, proj3) - @test point_vars ≈ point_vars_2 ≈ point_vars_3 + @test point_vars ≈ point_vars_2 ≈ point_vars_3 ≈ point_vars_4 if order == 1 # A linear approximation can not recover a quadratic solution, @@ -72,7 +74,12 @@ function test_projection(order, refshape) # Tensor f_tensor(x) = Tensor{2,2,Float64}((f(x),2*f(x),3*f(x),4*f(x))) qp_values = analytical(f_tensor) + qp_values_matrix = reduce(hcat, qp_values)::Matrix point_vars = project(proj, qp_values, qr) + point_vars_2 = project(proj, qp_values_matrix, qr) + + @test point_vars ≈ point_vars_2 + if order == 1 ae = [Tensor{2,2,Float64}((f_approx(i),2*f_approx(i),3*f_approx(i),4*f_approx(i))) for i in 1:4] elseif order == 2 @@ -83,7 +90,12 @@ function test_projection(order, refshape) # SymmetricTensor f_stensor(x) = SymmetricTensor{2,2,Float64}((f(x),2*f(x),3*f(x))) qp_values = analytical(f_stensor) + qp_values_matrix = reduce(hcat, qp_values) point_vars = project(proj, qp_values, qr) + point_vars_2 = project(proj, qp_values_matrix, qr) + + @test point_vars ≈ point_vars_2 + if order == 1 ae = [SymmetricTensor{2,2,Float64}((f_approx(i),2*f_approx(i),3*f_approx(i))) for i in 1:4] elseif order == 2 @@ -132,6 +144,7 @@ function test_projection_mixedgrid() ae = compute_vertex_values(mesh, f) # analytical values qp_values = [[f(spatial_coordinate(cv, qp, xe)) for qp in 1:getnquadpoints(cv)]] + qp_values_matrix = reduce(hcat, qp_values) # Now recover the nodal values using a L2 projection. # Assume f would only exist on the first cell, we project it to the nodes of the @@ -139,16 +152,18 @@ function test_projection_mixedgrid() # nodes that do not belong to the 1st cell proj = L2Projector(ip, mesh; geom_ip=ip_geom, set=1:1) point_vars = project(proj, qp_values, qr) + point_vars_2 = project(proj, qp_values_matrix, qr) ## Old API with fe values as first arg proj = @test_deprecated L2Projector(cv, ip, mesh, 1:1) - point_vars_2 = @test_deprecated project(qp_values, proj) + point_vars_3 = @test_deprecated project(qp_values, proj) ## Old API with qr as first arg proj = @test_deprecated L2Projector(qr, ip, mesh, 1:1) - point_vars_3 = @test_deprecated project(qp_values, proj) + point_vars_4 = @test_deprecated project(qp_values, proj) # In the nodes of the 1st cell we should recover the field for node in mesh.cells[1].nodes - @test ae[node] ≈ point_vars[node] ≈ point_vars_2[node] ≈ point_vars_3[node] + @test ae[node] ≈ point_vars[node] ≈ point_vars_2[node] ≈ point_vars_3[node] ≈ + point_vars_4[node] end # in all other nodes we should have NaNs @@ -157,6 +172,7 @@ function test_projection_mixedgrid() @test isnan(point_vars[node][d1, d2]) @test isnan(point_vars_2[node][d1, d2]) @test isnan(point_vars_3[node][d1, d2]) + @test isnan(point_vars_4[node][d1, d2]) end end end @@ -189,4 +205,4 @@ end test_projection(2, RefTetrahedron) test_projection_mixedgrid() test_node_reordering() -end \ No newline at end of file +end