feat: add plev, TensorTrain, tensor contraction, diag utilities

deps/build.jl

@@ -12,7 +12,7 @@ using Libdl
 using RustToolChain: cargo
 
 # Configuration
-const TENSOR4ALL_RS_FALLBACK_COMMIT = "4ee57fee0a71d385576c11d42850304548c6949d"
+const TENSOR4ALL_RS_FALLBACK_COMMIT = "3f05ea81177c64b5f351b99fdfd23325e732fc62"
 const TENSOR4ALL_RS_REPO = "https://github.com/tensor4all/tensor4all-rs.git"
 
 # Paths

ext/Tensor4allITensorsExt.jl

@@ -18,8 +18,8 @@ Both Rust and ITensors use UInt64 IDs natively, so conversion is direct.
 
 ## Memory Order
 
-Rust uses row-major, Julia/ITensors uses column-major.
-Conversion is handled automatically.
+Rust and Julia/ITensors use column-major order.
+Conversion preserves the logical layout.
 """
 module Tensor4allITensorsExt
 
@@ -40,12 +40,13 @@ IDs are natively UInt64 in both systems. Tags are preserved.
 function ITensors.Index(idx::Tensor4all.Index)
     d = Tensor4all.dim(idx)
     t = Tensor4all.tags(idx)
+    p = Tensor4all.plev(idx)
     id64 = Tensor4all.id(idx)
 
     # Create ITensors.Index with explicit ID using full constructor
     # Index(id, space, dir, tags, plev)
     tagset = isempty(t) ? ITensors.TagSet("") : ITensors.TagSet(t)
-    return ITensors.Index(id64, d, ITensors.Neither, tagset, 0)
+    return ITensors.Index(id64, d, ITensors.Neither, tagset, p)
 end
 
 # ============================================================================
@@ -65,12 +66,18 @@ cause an error.
 function Tensor4all.Index(idx::ITensors.Index)
     d = ITensors.dim(idx)
     id64 = ITensors.id(idx)
+    p = ITensors.plev(idx)
 
     # Get tags as comma-separated string
     tag_set = ITensors.tags(idx)
     tags_str = _tags_to_string(tag_set)
 
-    return Tensor4all.Index(d, id64; tags=tags_str)
+    t4a_idx = Tensor4all.Index(d, id64; tags=tags_str)
+    if p != 0
+        status = Tensor4all.C_API.t4a_index_set_plev(t4a_idx.ptr, Int64(p))
+        Tensor4all.C_API.check_status(status)
+    end
+    return t4a_idx
 end
 
 """

src/C_API.jl

@@ -272,6 +272,21 @@ function t4a_index_get_tags(ptr::Ptr{Cvoid}, buf, buf_len::Integer, out_len::Ref
     )
 end
 
+"""
+    t4a_index_get_plev(ptr::Ptr{Cvoid}, out_plev::Ref{Int64}) -> Cint
+
+Get the prime level of an index.
+"""
+function t4a_index_get_plev(ptr::Ptr{Cvoid}, out_plev::Ref{Int64})
+    return ccall(
+        _sym(:t4a_index_get_plev),
+        Cint,
+        (Ptr{Cvoid}, Ptr{Int64}),
+        ptr,
+        out_plev
+    )
+end
+
 # ============================================================================
 # Index modifiers
 # ============================================================================
@@ -322,6 +337,35 @@ function t4a_index_has_tag(ptr::Ptr{Cvoid}, tag::AbstractString)
     )
 end
 
+"""
+    t4a_index_set_plev(ptr::Ptr{Cvoid}, plev::Integer) -> Cint
+
+Set the prime level of an index.
+"""
+function t4a_index_set_plev(ptr::Ptr{Cvoid}, plev::Integer)
+    return ccall(
+        _sym(:t4a_index_set_plev),
+        Cint,
+        (Ptr{Cvoid}, Int64),
+        ptr,
+        Int64(plev)
+    )
+end
+
+"""
+    t4a_index_prime(ptr::Ptr{Cvoid}) -> Cint
+
+Increment the prime level of an index by 1.
+"""
+function t4a_index_prime(ptr::Ptr{Cvoid})
+    return ccall(
+        _sym(:t4a_index_prime),
+        Cint,
+        (Ptr{Cvoid},),
+        ptr
+    )
+end
+
 # ============================================================================
 # Storage kind enum
 # ============================================================================
@@ -541,6 +585,22 @@ function t4a_tensor_onehot(rank::Integer, index_ptrs::Vector{Ptr{Cvoid}}, vals::
     )
 end
 
+"""
+    t4a_tensor_contract(a::Ptr{Cvoid}, b::Ptr{Cvoid}, out::Ref{Ptr{Cvoid}})
+
+Contract two tensors and write the resulting tensor handle to `out`.
+"""
+function t4a_tensor_contract(a::Ptr{Cvoid}, b::Ptr{Cvoid}, out::Ref{Ptr{Cvoid}})
+    return ccall(
+        _sym(:t4a_tensor_contract),
+        Cint,
+        (Ptr{Cvoid}, Ptr{Cvoid}, Ptr{Ptr{Cvoid}}),
+        a,
+        b,
+        out
+    )
+end
+
 # ============================================================================
 # TreeTN lifecycle functions
 # ============================================================================