[GNNLux] TGCN temporal layer (#470)

* First draft

* Fix signature

* Improvement

* Export TGCN

* Fixes

* Back to previous version

* Add test

* Remove GNNlib code

* Fix

* Fix

Co-authored-by: Carlo Lucibello <[email protected]>

---------

Co-authored-by: Carlo Lucibello <[email protected]>

GNNLux/src/GNNLux.jl

@@ -37,7 +37,9 @@ export AGNNConv,
        SGConv
        # TAGConv,
        # TransformerConv
-
+
+include("layers/temporalconv.jl")
+export TGCN
 
 end #module
 

GNNLux/src/layers/temporalconv.jl

@@ -0,0 +1,59 @@
+@concrete struct StatefulRecurrentCell <: AbstractExplicitContainerLayer{(:cell,)}     
+    cell <: Union{<:Lux.AbstractRecurrentCell, <:GNNContainerLayer}
+end
+
+function LuxCore.initialstates(rng::AbstractRNG, r::GNNLux.StatefulRecurrentCell)
+    return (cell=LuxCore.initialstates(rng, r.cell), carry=nothing)
+end
+
+function (r::StatefulRecurrentCell)(g, x::AbstractMatrix, ps, st::NamedTuple)
+    (out, carry), st = applyrecurrentcell(r.cell, g, x, ps, st.cell, st.carry)
+    return out, (; cell=st, carry)
+end
+
+function (r::StatefulRecurrentCell)(g, x::AbstractVector, ps, st::NamedTuple)
+    st, carry = st.cell, st.carry
+    for xᵢ in x
+        (out, carry), st = applyrecurrentcell(r.cell, g, xᵢ, ps, st, carry)
+    end
+    return out, (; cell=st, carry)
+end
+
+function applyrecurrentcell(l, g, x, ps, st, carry)
+    return Lux.apply(l, g, (x, carry), ps, st)
+end
+
+LuxCore.apply(m::GNNContainerLayer, g, x, ps, st) = m(g, x, ps, st)
+
+@concrete struct TGCNCell <: GNNContainerLayer{(:conv, :gru)}
+    in_dims::Int
+    out_dims::Int
+    conv
+    gru
+    init_state::Function
+end
+
+function TGCNCell(ch::Pair{Int, Int}; use_bias = true, init_weight = glorot_uniform, init_state = zeros32, init_bias = zeros32, add_self_loops = false, use_edge_weight = true) 
+    in_dims, out_dims = ch
+    conv = GCNConv(ch, sigmoid; init_weight, init_bias, use_bias, add_self_loops, use_edge_weight, allow_fast_activation= true)
+    gru = Lux.GRUCell(out_dims => out_dims; use_bias, init_weight = (init_weight, init_weight, init_weight), init_bias = (init_bias, init_bias, init_bias), init_state = init_state)
+    return TGCNCell(in_dims, out_dims, conv, gru, init_state)
+end
+
+function (l::TGCNCell)(g, (x, h), ps, st)
+    if h === nothing
+        h = l.init_state(l.out_dims, 1)
+    end
+    x̃, stconv = l.conv(g, x, ps.conv, st.conv)
+    (h, (h,)), stgru = l.gru((x̃,(h,)), ps.gru,st.gru)
+    return  (h, h), (conv=stconv, gru=stgru)
+end
+
+LuxCore.outputsize(l::TGCNCell) = (l.out_dims,)
+LuxCore.outputsize(l::GNNLux.StatefulRecurrentCell) = (l.cell.out_dims,)
+
+function Base.show(io::IO, tgcn::TGCNCell)
+    print(io, "TGCNCell($(tgcn.in_dims) => $(tgcn.out_dims))")
+end
+
+TGCN(ch::Pair{Int, Int}; kwargs...) = GNNLux.StatefulRecurrentCell(TGCNCell(ch; kwargs...))

GNNLux/test/layers/temporalconv_test.jl

@@ -0,0 +1,15 @@
+@testitem "layers/temporalconv" setup=[SharedTestSetup] begin
+    using LuxTestUtils: test_gradients, AutoReverseDiff, AutoTracker, AutoForwardDiff, AutoEnzyme
+
+    rng = StableRNG(1234)
+    g = rand_graph(10, 40, seed=1234)
+    x = randn(rng, Float32, 3, 10)
+
+    @testset "TGCN" begin
+        l = TGCN(3=>3)
+        ps = LuxCore.initialparameters(rng, l)
+        st = LuxCore.initialstates(rng, l)
+        loss = (x, ps) -> sum(first(l(g, x, ps, st)))
+        test_gradients(loss, x, ps; atol=1.0f-2, rtol=1.0f-2, skip_backends=[AutoReverseDiff(), AutoTracker(), AutoForwardDiff(), AutoEnzyme()])
+    end
+end

GNNlib/src/GNNlib.jl

@@ -61,7 +61,7 @@ export agnn_conv,
        transformer_conv
 
 include("layers/temporalconv.jl")
-export a3tgcn_conv
+export tgcn_conv
 
 include("layers/pool.jl")
 export global_pool,