Compatibility with multifusion categories

src/algorithms/toolbox.jl

@@ -28,7 +28,7 @@ Return the density matrix of the infinite temperature state for a given Hamilton
 This is the identity matrix in the physical space, and the identity in the auxiliary space.
 """
 function infinite_temperature_density_matrix(H::MPOHamiltonian)
-    V = oneunit(spacetype(H))
+    V = oneunit(space(first(H[1]), 1))
     W = map(1:length(H)) do site
         return BraidingTensor{scalartype(H)}(physicalspace(H, site), V)
     end

src/operators/mpohamiltonian.jl

@@ -388,7 +388,7 @@ function FiniteMPOHamiltonian(lattice::AbstractArray{<:VectorSpace}, local_opera
     somempo = local_mpos[1].second[1]
     sp_oneleg = space(somempo, 1)
 
-    _oneunit = oneunit(sp_oneleg)
+    _oneunit = oneunit(sp_oneleg) # should be rightoneunit, but MPOHamiltonians are always diagonal for now
 
     virtualsumspaces = Vector{SumSpace{S}}(undef, length(lattice) + 1)
     virtualsumspaces[1] = SumSpace(fill(_oneunit, 1))
@@ -669,7 +669,7 @@ function Base.:+(
     ) where {O <: JordanMPOTensor}
     N = check_length(H₁, H₂)
     H = similar(parent(H₁))
-    Vtriv = oneunit(space(first(H₁[1]), 1))
+    Vtriv = oneunit(space(first(H₁[1]), 1)) # should also be rightoneunit, but is currently diagonal
 
     for i in 1:N
         A = cat(H₁[i].A, H₂[i].A; dims = (1, 4))

src/utility/utility.jl

@@ -73,7 +73,8 @@ function add_util_mpoleg(tensor::AbstractTensorMap{T, S, N1, N2}) where {T, S, N
     # separate function for mpo because add_util_leg is also used for mps from tensors
     # and the additional legs there can be different depending on the fusion tree
 
-    ou = Vect[sectortype(_firstspace(tensor))](one(first(sectors(_firstspace(tensor)))) => 1)
+    #TODO?: might need a left and right utility space if MPO has module virtual space (doesn't happen for hamiltonians)
+    ou = S(one(first(blocksectors(tensor))) => 1)
 
     util_front = isomorphism(storagetype(tensor), ou * codomain(tensor), codomain(tensor))
     util_back = isomorphism(storagetype(tensor), domain(tensor), domain(tensor) * ou)