Add reverse Index map to ITensorNetwork; drop preserve_graph and fix_edges!

docs/src/experimental_methods.md

@@ -37,9 +37,8 @@ Methods which still need to be discussed, modified, or deprecated.
 
 #### AbstractTreeTensorNetwork Type
 
-* Required-to-implement abstract interface — `TreeTensorNetwork` provides all three (`treetensornetworks/abstracttreetensornetwork.jl`):
+* Required-to-implement abstract interface — `TreeTensorNetwork` provides both (`treetensornetworks/abstracttreetensornetwork.jl`):
   ```julia
-  ITensorNetwork(tn::AbstractTTN)
   ortho_region(tn::AbstractTTN)
   set_ortho_region(tn::AbstractTTN, new_region)
   ```
@@ -134,11 +133,6 @@ Methods which still need to be discussed, modified, or deprecated.
 
 #### TreeTensorNetwork Type
 
-* Get the underlying `ITensorNetwork` of a `TTN` (drops orthogonality metadata) (`treetensornetworks/treetensornetwork.jl`):
-  ```julia
-  ITensorNetwork(tn::TTN)
-  ```
-
 * Get the current orthogonality region — the set of vertices forming the gauge center (`treetensornetworks/treetensornetwork.jl`):
   ```julia
   ortho_region(tn::TTN)

docs/src/interface_methods.md

@@ -15,14 +15,6 @@ These ITensorNetwork constructor interfaces are foundational to other constructo
   ITensorNetwork{V}(tensors)
   ```
 
-* From a collection of `ITensor`s placed at the vertices of a given `NamedGraph`. No
-  edge inference; the graph's edges are used as-is.
-  ```julia
-  ITensorNetwork(tensors, graph::NamedGraph)
-  ITensorNetwork{V}(tensors, graph::NamedGraph)
-  ```
-
-
 ## Analyzing ITensorNetworks
 
 
@@ -65,12 +57,10 @@ These ITensorNetwork constructor interfaces are foundational to other constructo
 
 ## Global Operations on ITensorNetworks
 
-* Scale tensors at chosen vertices by per-vertex weights, either out-of-place or in-place (`abstractitensornetwork.jl`).
+* Map a function over the vertex tensors of an `ITensorNetwork`, returning a copy
+  (`abstractitensornetwork.jl`):
   ```julia
-  scale_tensors(tn::AbstractITensorNetwork, vertices_weights::Dictionary; kwargs...)
-  scale_tensors(weight_function::Function, tn; kwargs...)
-  scale_tensors!(tn::AbstractITensorNetwork, vertices_weights::Dictionary)
-  scale_tensors!(weight_function::Function, tn::AbstractITensorNetwork; kwargs...)
+  map(f, tn::AbstractITensorNetwork)
   ```
 
 * Tensor product (disjoint union) of two ITensorNetworks (`abstractitensornetwork.jl`):

docs/src/itensor_networks.md

@@ -56,7 +56,7 @@ tensors = Dict(map(collect(vertices(g))) do v
     return v => random_itensor(site_v..., link_v...)
 end)
 
-ψ = ITensorNetwork(tensors, g)
+ψ = ITensorNetwork(tensors)
 ```
 
 Higher-level construction routines (random networks, product states, OpSum-derived

docs/src/solvers.md

@@ -30,7 +30,7 @@ function random_state(g, s; link_space)
         v => random_itensor(only(s[v]), (l[e] for e in incident_edges(g, v))...)
             for v in vertices(g)
     )
-    return ITensorNetwork(ts, g)
+    return ITensorNetwork(ts)
 end
 
 # Build a Heisenberg Hamiltonian on a comb tree

docs/src/tree_tensor_networks.md

@@ -53,7 +53,7 @@ tensors = Dict(map(collect(vertices(g))) do v
     link_v = [haskey(links, e) ? links[e] : links[reverse(e)] for e in incident_edges(g, v)]
     return v => random_itensor(site_v..., link_v...)
 end)
-itn = ITensorNetwork(tensors, g)
+itn = ITensorNetwork(tensors)
 psi = TreeTensorNetwork(itn)
 ```
 
@@ -65,7 +65,6 @@ itn_again = ITensorNetwork(psi)  # TTN → ITensorNetwork
 
 ```@docs; canonical=false
 ITensorNetworks.TreeTensorNetwork
-ITensorNetworks.ITensorNetwork(::ITensorNetworks.TreeTensorNetwork)
 ```
 
 ## Orthogonal Gauge