From e3965efa2c0b55bb1e7c16739690d8769d02636e Mon Sep 17 00:00:00 2001
From: LHerviou <loic.herviou@epfl.ch>
Date: Mon, 26 Jun 2023 10:11:38 +0200
Subject: [PATCH 1/2] Testing with newest ITensor

---
 src/ITensors.jl          | 14 +++++++-------
 src/infinitempo.jl       | 10 ----------
 src/infinitempomatrix.jl | 24 ++++++++++++------------
 3 files changed, 19 insertions(+), 29 deletions(-)

diff --git a/src/ITensors.jl b/src/ITensors.jl
index 1eca3907..61d4f856 100644
--- a/src/ITensors.jl
+++ b/src/ITensors.jl
@@ -183,13 +183,13 @@ end
 # Handle orthogonality center correctly
 Base.getindex(ψ::MPS, r::UnitRange{Int}) = MPS([ψ[n] for n in r])
 
-Base.zero(T::ITensor) = false * T
-
-function ITensors.NDTensors.datatype(
-  ::ITensors.EmptyStorage{Float64,ITensors.NDTensors.BlockSparse{Float64,Vector{Float64},N}}
-) where {N}
-  return Vector{Float64}
-end
+# Base.zero(T::ITensor) = false * T
+#
+# function ITensors.NDTensors.datatype(
+#   ::ITensors.EmptyStorage{Float64,ITensors.NDTensors.BlockSparse{Float64,Vector{Float64},N}}
+# ) where {N}
+#   return Vector{Float64}
+# end
 #
 # function ITensors.NDTensors.datatype(T::ITensors.NDTensors.TensorStorage{Float64})
 #   return typeof(data(T))
diff --git a/src/infinitempo.jl b/src/infinitempo.jl
index fd8c7776..abf89670 100644
--- a/src/infinitempo.jl
+++ b/src/infinitempo.jl
@@ -44,11 +44,6 @@ function cat_to_itensor(Hm::Matrix{ITensor})
     end
     append!(input, [Hm[x, ly] * onehot(T, right_links[ly] => 1) => right_links[ly]])
     H, ir = directsum(input...; tags="Link, right")
-    # H, ir = directsum(
-    #   [((y == 1 || y == ly) ? Hm[x, y] * onehot(T, right_links[y] => 1) : Hm[x, y]) =>
-    #     right_links[y] for y in 1:ly]...;
-    #   tags="Link, right",
-    # )
     if x == 1
       append!(new_rs, [ir])
     else
@@ -62,11 +57,6 @@ function cat_to_itensor(Hm::Matrix{ITensor})
   end
   append!(input, [Ls[lx] * onehot(T, left_links[lx] => 1) => left_links[lx]])
   H, new_l = directsum(input...; tags="Link, left")
-  # H, new_l = directsum(
-  #   [((x == 1 || x == lx) ? Ls[x] * onehot(T, left_links[x] => 1) : Ls[x]) => left_links[x] for
-  #    x in 1:lx]...;
-  #   tags="Link, left",
-  # )
   return H, new_l, new_rs[1]
 end
 #
diff --git a/src/infinitempomatrix.jl b/src/infinitempomatrix.jl
index 25eaf8cf..2522af84 100644
--- a/src/infinitempomatrix.jl
+++ b/src/infinitempomatrix.jl
@@ -220,15 +220,15 @@ function apply_tensor(A::Array{ITensor,N}, B::ITensor...) where {N}
   return new_A
 end
 
-import ITensors._add
-function ITensors._add(
-  A::T1, B::T2
-) where {T1<:ITensors.NDTensors.EmptyTensor,T2<:ITensors.NDTensors.EmptyTensor}
-  ndims(A) != ndims(B) && throw(
-    ITensors.DimensionMismatch("cannot add ITensors with different numbers of indices")
-  )
-  indices = inds(A)
-  length(commoninds(indices, B)) != length(inds(B)) &&
-    error("cannot add ITensors with different indices")
-  return ITensor(promote_type(eltype(A), eltype(B)), indices)
-end
+# import ITensors._add
+# function ITensors._add(
+#   A::T1, B::T2
+# ) where {T1<:ITensors.NDTensors.EmptyTensor,T2<:ITensors.NDTensors.EmptyTensor}
+#   ndims(A) != ndims(B) && throw(
+#     ITensors.DimensionMismatch("cannot add ITensors with different numbers of indices")
+#   )
+#   indices = inds(A)
+#   length(commoninds(indices, B)) != length(inds(B)) &&
+#     error("cannot add ITensors with different indices")
+#   return ITensor(promote_type(eltype(A), eltype(B)), indices)
+# end

From d9bdba50b0fc69a82d2fe2d9383c127691c324d1 Mon Sep 17 00:00:00 2001
From: LHerviou <loic.herviou@epfl.ch>
Date: Mon, 26 Jun 2023 11:08:55 +0200
Subject: [PATCH 2/2] Testing the fix

---
 src/ITensors.jl | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/ITensors.jl b/src/ITensors.jl
index 61d4f856..ec8310bd 100644
--- a/src/ITensors.jl
+++ b/src/ITensors.jl
@@ -194,3 +194,5 @@ Base.getindex(ψ::MPS, r::UnitRange{Int}) = MPS([ψ[n] for n in r])
 # function ITensors.NDTensors.datatype(T::ITensors.NDTensors.TensorStorage{Float64})
 #   return typeof(data(T))
 # end
+
+Base.fill!(::NDTensors.NoData, ::Any) = 0