Remove new_group_axis from space groups

src/space_groups.jl

@@ -5,21 +5,20 @@ Each space group is defined by a point group and a way of using it to act on a g
 """
 struct SpaceGroup{I}
     point_group::PointGroup
-    new_group_axis::Int
 end
 
-const P1 = SpaceGroup{:P1}(C1, 1)
-const P2 = SpaceGroup{:P2}(C2, 1)
-const P2MM = SpaceGroup{:P2MM}(D2, 1)
-const P4 = SpaceGroup{:P4}(C4, 1)
-const P4M = SpaceGroup{:P4M}(D4, 1)
+const P1 = SpaceGroup{:P1}(C1)
+const P2 = SpaceGroup{:P2}(C2)
+const P2MM = SpaceGroup{:P2MM}(D2)
+const P4 = SpaceGroup{:P4}(C4)
+const P4M = SpaceGroup{:P4M}(D4)
 
 SpaceGroups = [P1, P2, P2MM, P4, P4M]
 
 
-function (g::SpaceGroup)(x::AbstractArray, axes::AxesInfo)
-    x, axes = lift(x, axes, g.new_group_axis)
-    x = act_on_grid(g, x, axes)
+function (g::SpaceGroup)(x::AbstractArray, axes::AxesInfo, new_group_axis::Int)
+    x, axes = lift(x, axes, new_group_axis)
+    x = act_on_grid(g, x, axes, new_group_axis)
     # TODO: acting on group
     x
 end
@@ -31,49 +30,50 @@ Apply a space group to a grid.
 - `g`: The group to apply.
 - `x`: The grid to act on.
 - `axes`: The meaning of the axes of the grid.
+- `new_group_axis`: The axis on which group actions should be concatenated.
 
 # Returns
 The grid after the group action has been applied.
 """
-function act_on_grid(g::SpaceGroup, x::AbstractArray, axes::AxesInfo) end
+function act_on_grid(g::SpaceGroup, x::AbstractArray, axes::AxesInfo, new_group_axis::Int) end
 
-function act_on_grid(g::SpaceGroup{:P1}, x::AbstractArray, axes::AxesInfo)
+function act_on_grid(g::SpaceGroup{:P1}, x::AbstractArray, axes::AxesInfo, new_group_axis::Int)
     x
 end
 
-function act_on_grid(g::SpaceGroup{:P2}, x::AbstractArray, axes::AxesInfo)
+function act_on_grid(g::SpaceGroup{:P2}, x::AbstractArray, axes::AxesInfo, new_group_axis::Int)
     x_rotated = reverse(x, dims = (axes.width, axes.height))
-    x = cat(x, x_rotated, dims = g.new_group_axis)
+    x = cat(x, x_rotated, dims = new_group_axis)
     x
 end
 
-function act_on_grid(g::SpaceGroup{:P2MM}, x::AbstractArray, axes::AxesInfo)
-    x = cat(x, reverse(x, dims = axes.height), dims = g.new_group_axis)
-    x = cat(x, reverse(x, dims = axes.width), dims = g.new_group_axis)
+function act_on_grid(g::SpaceGroup{:P2MM}, x::AbstractArray, axes::AxesInfo, new_group_axis::Int)
+    x = cat(x, reverse(x, dims = axes.height), dims = new_group_axis)
+    x = cat(x, reverse(x, dims = axes.width), dims = new_group_axis)
     x
 end
 
-function act_on_grid(g::SpaceGroup{:P4}, x::AbstractArray, axes::AxesInfo)
-    x = cat(x, reverse(x, dims = (axes.width, axes.height)), dims = g.new_group_axis)
+function act_on_grid(g::SpaceGroup{:P4}, x::AbstractArray, axes::AxesInfo, new_group_axis::Int)
+    x = cat(x, reverse(x, dims = (axes.width, axes.height)), dims = new_group_axis)
     x = cat(
         x,
         reverse(swap_axes(x, axes.width, axes.height), dims = axes.height),
-        dims = g.new_group_axis,
+        dims = new_group_axis,
     )
     # put the elements in the right order
     order = [1, 3, 2, 4]
-    indices = ntuple(a -> a == g.new_group_axis ? order : :, ndims(x))
+    indices = ntuple(a -> a == new_group_axis ? order : :, ndims(x))
     x = x[indices...]
     x
 end
 
-function act_on_grid(g::SpaceGroup{:P4M}, x::AbstractArray, axes::AxesInfo)
-    x = cat(x, reverse(x, dims = axes.width), dims = g.new_group_axis)
-    x = cat(x, reverse(x, dims = axes.height), dims = g.new_group_axis)
-    x = cat(x, swap_axes(x, axes.width, axes.height), dims = g.new_group_axis)
+function act_on_grid(g::SpaceGroup{:P4M}, x::AbstractArray, axes::AxesInfo, new_group_axis::Int)
+    x = cat(x, reverse(x, dims = axes.width), dims = new_group_axis)
+    x = cat(x, reverse(x, dims = axes.height), dims = new_group_axis)
+    x = cat(x, swap_axes(x, axes.width, axes.height), dims = new_group_axis)
     # put the elements in the right order
     order = [1, 6, 4, 7, 2, 5, 3, 8]
-    indices = ntuple(a -> a == g.new_group_axis ? order : :, ndims(x))
+    indices = ntuple(a -> a == new_group_axis ? order : :, ndims(x))
     x = x[indices...]
     x
 end

test/actiontests.jl

@@ -1,22 +1,23 @@
 function test_action_composition(space_group::SpaceGroup, x::AbstractArray, axes::AxesInfo)
+    new_group_axis = 1
     point_group = space_group.point_group
-    g_x = space_group(x, axes)
+    g_x = space_group(x, axes, new_group_axis)
 
     # This is when acting two times, first with the element at axis 1, then at axis 2
     # here we need to take care of the axes explicitly
-    _, axes = lift(x, axes, space_group.new_group_axis)
-    # Now the h axis is action.new_group_axis and the g axis is action.new_group_axis + 1
-    h_on_g_x = space_group(g_x, axes)
+    _, axes = lift(x, axes, new_group_axis)
+    # Now the h axis is new_group_axis and the g axis is new_group_axis + 1
+    h_on_g_x = space_group(g_x, axes, new_group_axis)
 
     # Now first compose the point group elements, then act once
     # flattened list of compositions
     h_compose_g = reshape(point_group.composition, :)
-    indices = ntuple(a -> a == space_group.new_group_axis ? h_compose_g : :, ndims(g_x))
+    indices = ntuple(a -> a == new_group_axis ? h_compose_g : :, ndims(g_x))
     h_g_on_x = g_x[indices...]
     # This has the actions of all 2 group element compositions on one axis,
     # so we need to spread them over two axes again
     h_g_on_x = reshape(h_g_on_x, size(h_on_g_x)...)
 
     # Check if the two are equal
     @test all(h_on_g_x .=== h_g_on_x)
-end
+end