ITensorBase extension to construct ITensors

Author: mtfishman

Project.toml

@@ -7,7 +7,14 @@ version = "0.1.3"
 LinearAlgebra = "37e2e46d-f89d-539d-b4ee-838fcccc9c8e"
 Random = "9a3f8284-a2c9-5f02-9a11-845980a1fd5c"
 
+[weakdeps]
+ITensorBase = "4795dd04-0d67-49bb-8f44-b89c448a1dc7"
+
+[extensions]
+QuantumOperatorDefinitionsITensorBaseExt = "ITensorBase"
+
 [compat]
+ITensorBase = "0.1.10"
 LinearAlgebra = "1.10"
 Random = "1.10"
 julia = "1.10"

ext/QuantumOperatorDefinitionsITensorBaseExt/QuantumOperatorDefinitionsITensorBaseExt.jl

@@ -0,0 +1,24 @@
+module QuantumOperatorDefinitionsITensorBaseExt
+
+using ITensorBase: ITensor, Index, dag, gettag, prime
+using QuantumOperatorDefinitions:
+  QuantumOperatorDefinitions, OpName, SiteType, StateName, has_fermion_string
+
+function QuantumOperatorDefinitions.SiteType(r::Index)
+  return SiteType(gettag(r, "sitetype", "Qudit"); length=Int(length(r)))
+end
+
+function QuantumOperatorDefinitions.has_fermion_string(n::String, r::Index)
+  return has_fermion_string(OpName(n), SiteType(r))
+end
+
+function Base.AbstractArray(n::OpName, r::Index)
+  # TODO: Define this with mapped dimnames.
+  return ITensor(AbstractArray(n, SiteType(r)), (prime(r), dag(r)))
+end
+
+function Base.AbstractArray(n::StateName, r::Index)
+  return ITensor(AbstractArray(n, SiteType(r)), (r,))
+end
+
+end

test/test_itensorbaseext.jl

@@ -0,0 +1,13 @@
+using ITensorBase: ITensor, Index, prime
+using QuantumOperatorDefinitions: op, state
+using Test: @test, @testset
+
+@testset "QuantumOperatorDefinitionsITensorBaseExt" begin
+  i = Index(2)
+
+  a = op("X", i)
+  @test a == ITensor([0 1; 1 0], (prime(i), i))
+
+  a = state(1, i)
+  @test a == ITensor([1, 0], (i,))
+end