fix subgrid coordinate system for boundary grids (#38)

* fix subgrid coordinate system for boundary grids

* use ExampleJuggler v2 (no Pluto dependency due to extensions)

Project.toml

@@ -1,7 +1,7 @@
 name = "ExtendableGrids"
 uuid = "cfc395e8-590f-11e8-1f13-43a2532b2fa8"
 authors = ["Juergen Fuhrmann <[email protected]>", "Christian Merdon  <[email protected]>", "Johannes Taraz  <[email protected]>"]
-version = "1.3.0"
+version = "1.3.1"
 
 [deps]
 AbstractTrees = "1520ce14-60c1-5f80-bbc7-55ef81b5835c"

docs/Project.toml

@@ -12,3 +12,4 @@ Triangulate = "f7e6ffb2-c36d-4f8f-a77e-16e897189344"
 [compat]
 Documenter = "1"
 julia = "1.9"
+ExampleJuggler = "2"

src/coordinatesystem.jl

@@ -69,3 +69,15 @@ abstract type Spherical1D   <: AbstractCoordinateSystem end  #r (integral over 
 
 
 const CoordinateSystems=Union{[Type{t} for t in leaftypes(AbstractCoordinateSystem)]...}
+
+
+"""
+    codim1_coordinatesystem(CoordinateSystem)
+
+Return coordinate system for codimension 1 subgrid.
+"""
+codim1_coordinatesystem(::Type{T}) where T<:AbstractCoordinateSystem = nothing
+codim1_coordinatesystem(::Type{Cartesian3D})=Cartesian2D
+codim1_coordinatesystem(::Type{Cartesian2D})=Cartesian1D
+
+

src/subgrid.jl

@@ -62,18 +62,6 @@ Grid component key type for indicating that grid is a refinement of the parentgr
 """
 abstract type RefinedGrid <: ParentGridRelation end
 
-
-"""
-$(TYPEDSIGNATURES)
-
-Default transform for subgrid creation
-"""
-function _copytransform!(a::AbstractArray,b::AbstractArray)
-    for i=1:length(a)
-        a[i]=b[i]
-    end
-end
-
 struct XIPair{Tv, Ti}
     x::Tv
     i::Ti
@@ -85,16 +73,23 @@ Base.isless(x::XIPair, y::XIPair) = (x.x < y.x)
 
 
 """
-$(TYPEDSIGNATURES)
+    subgrid(parent,                                                             
+            subregions::AbstractArray;                                          
+            transform::T=function(a,b) @views a.=b[1:length(a)] end,                                      
+            boundary=false,                                                     
+            coordinatesystem=codim1_coordinatesystem(parent[CoordinateSystem]), 
+            project=true) where T                                               
 
 Create subgrid from list of regions.
 
 - `parent`: parent grid 
-- `subregions`:  Array of subregions
+- `subregions`:  Array of subregions which define the subgrid
+- `boundary`: if true, create codimension 1 subgrid from boundary regions.
 - `transform` (kw parameter): transformation function between
    grid and subgrid coordinates acting on one point.
-   Default: `copytransform`
-- `boundary`: if true, create codimension 1 subgrid from boundary region.
+- `coordinatesystem`: if `boundary==true`, specify coordinate system for the boundary.
+   Default:  if parent coordinatesystem is cartesian, just the cooresponding codim1 coordinatesystem, 
+   otherwise: `nothing`, requiring user specification for use of e.g. CellFinder with the subgrid.
 - `project`: project coordinates onto  subgrid dimension
 
 A subgrid is of type `ExtendableGrid` and stores two additional components:
@@ -103,9 +98,10 @@ A subgrid is of type `ExtendableGrid` and stores two additional components:
 """
 function subgrid(parent,
                  subregions::AbstractArray;
-                 transform::Function=_copytransform!,
+                 transform::T=function(a,b) @views a.=b[1:length(a)] end,                                      
                  boundary=false,
-                 project=true)
+                 coordinatesystem=codim1_coordinatesystem(parent[CoordinateSystem]),
+                 project=true) where T
 
     Tc=coord_type(parent)
     Ti=index_type(parent)
@@ -205,6 +201,9 @@ function subgrid(parent,
         subgrid[BFaceGeometries]=ElementGeometries[]
         subgrid[BFaceNodes]=Matrix{Ti}(undef,sub_gdim,0)
         subgrid[NumBFaceRegions]=0
+        if !isnothing(coordinatesystem)
+            subgrid[CoordinateSystem]=coordinatesystem
+        end
     else
         bfacenodes=parent[BFaceNodes]
         bfaceregions=parent[BFaceRegions]
@@ -258,8 +257,8 @@ function subgrid(parent,
             subgrid[BFaceNodes]=zeros(Ti, 2, 0)
             subgrid[NumBFaceRegions]=0
         end
+        subgrid[CoordinateSystem]=parent[CoordinateSystem]
     end
-    subgrid[CoordinateSystem]=parent[CoordinateSystem]
 
     if sub_gdim == 1
         # Sort nodes of grid for easy plotting

test/Project.toml

@@ -8,4 +8,4 @@ Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40"
 Triangulate = "f7e6ffb2-c36d-4f8f-a77e-16e897189344"
 
 [compat]
-ExampleJuggler = "0.4"
+ExampleJuggler = "2"

test/runtests.jl

@@ -1,7 +1,8 @@
-using Test, ExampleJuggler
-using ExtendableGrids, SHA
+using Test
 
-ExampleJuggler.verbose!(true)
+using ExampleJuggler
+
+using ExtendableGrids, SHA
 
 @testset "Geomspace" begin
     function test_geomspace()
@@ -263,6 +264,9 @@ end
 
 include("gmsh.jl")
 
+
+ExampleJuggler.verbose!(true)
+
 @testset "Examples" begin
     @testscripts(joinpath(@__DIR__, "..", "examples"), ["examples1d.jl", "examples2d.jl", "examples3d.jl", "gmsh.jl"])
 end

test/test_gridstuff.jl

@@ -78,6 +78,7 @@ function check_cellfinder(xgrid)
     EG = xgrid[UniqueCellGeometries]
     @info "Testing CellFinder for geometries=$EG..."
     xCoordinates = xgrid[Coordinates]
+    @show xCoordinates
     xCellNodes = xgrid[CellNodes]
     edim = dim_element(EG[1])
     CF::CellFinder{Float64,Int32} = CellFinder(xgrid)
@@ -89,11 +90,11 @@ function check_cellfinder(xgrid)
         x_source[j] += xCoordinates[j,xCellNodes[k,cell_to_find]] + 1e-6
     end
     x_source ./= num_targets(xCellNodes,cell_to_find)
-
+    @show x_source
     # find cell by local strategy
     xref = zeros(Float64,edim+1)
     cell = gFindLocal!(xref, CF, x_source; icellstart = 1)
-
+    
     # check xref
     x = zeros(Float64,edim)
     L2G = L2GTransformer(xgrid[CellGeometries][cell], xgrid, ON_CELLS)
@@ -151,6 +152,17 @@ function run_grid_tests()
     @test check_cellfinder(get_testgrid(Tetrahedron3D))
     @test check_cellfinder(get_testgrid(Parallelepiped3D))
 
+    X = LinRange(0, 1, 10)
+    grid = simplexgrid(X, X)
+    sub = subgrid(grid, [2], transform=function(a,b) a[1]=b[2] end,  boundary=true)
+    @test check_cellfinder(sub)
+
+    grid = simplexgrid(X, X, X)
+    sub = subgrid(grid, [5], boundary=true)
+    @test check_cellfinder(sub)
+
+
+
     @test check_uniform_refinement(reference_domain(Triangle2D), false)
     @test check_uniform_refinement(reference_domain(Triangle2D), true)
     @test check_uniform_refinement(reference_domain(Parallelogram2D), false)