Remove size type parameter from ITensor and IndexSet (#591)

* Remove size type parameter from ITensor and IndexSet, use Vector as storage for IndexSet

* Remove Order-based set functions

* Add ability to add and subtract emptyITensor() (replaces using emptyITensor(Any) for this purpose)

Co-authored-by: Miles Stoudenmire <[email protected]>

Author: kshyatt

benchmark/bench_indexset.jl

@@ -15,9 +15,7 @@ suite["constructor"]["function"] = @benchmarkable IndexSet($(n -> i^(n-1)), $(Or
 suite["filter"] = BenchmarkGroup()
 
 suite["filter"]["kwargs"] = @benchmarkable filter($is; plev = 3)
-suite["filter"]["order_kwargs"] = @benchmarkable filter($(Order(1)), $is; plev = 3)
 suite["filter"]["function"] = @benchmarkable filter($(i -> plev(i) < 2), $is)
-suite["filter"]["function_order"] = @benchmarkable filter($(i -> plev(i) < 2), $(Order(2)), $is)
 
 i,j,k,l = Index.(2, ("i", "j", "k", "l"))
 
@@ -33,11 +31,6 @@ suite["uniqueinds"]["nofilter0"] = @benchmarkable uniqueinds($Iij, $Iijk)
 suite["uniqueinds"]["filter_tags"] = @benchmarkable uniqueinds($Iijk, $Ikl; tags = $(ts"i"))
 suite["uniqueinds"]["filter_not_tags"] = @benchmarkable uniqueinds($Iijk, $Ikl; tags = $(not("i")))
 suite["uniqueinds"]["3_inputs"] = @benchmarkable uniqueinds($Iijk, $Ijl, $Ikl)
-suite["uniqueinds"]["order2"] = @benchmarkable uniqueinds($(Order(2)), $Iijk, $Ikl)
-suite["uniqueinds"]["order0"] = @benchmarkable uniqueinds($(Order(0)), $Iij, $Iijk)
-suite["uniqueinds"]["order_filter_tags"] = @benchmarkable uniqueinds($(Order(1)), $Iijk, $Ikl; tags = $(ts"i"))
-suite["uniqueinds"]["order_filter_not_tags"] = @benchmarkable uniqueinds($(Order(1)), $Iijk, $Ikl; tags = $(not("i")))
-suite["uniqueinds"]["order_3_inputs"] = @benchmarkable uniqueinds($(Order(1)), $Iijk, $Ijl, $Ikl)
 
 end
 

docs/src/AdvancedUsageGuide.md

@@ -756,8 +756,8 @@ Advanced users might notice something strange about the definition
 of the ITensor type, that it is often not "type stable". Some of 
 this is by design. The definition for ITensor is:
 ```julia
-mutable struct ITensor{N}
-  inds::IndexSet{N}
+mutable struct ITensor
+  inds::IndexSet
   store::TensorStorage
 end
 ```
@@ -774,7 +774,7 @@ julia> A = randomITensor(i, i');
 julia> @code_warntype A[i=>1, i'=>2]
 Variables
   #self#::Core.Compiler.Const(getindex, false)
-  T::ITensor{1}
+  T::ITensor
   ivs::Tuple{Pair{Index{Int64},Int64}}
   p::Tuple{Union{Nothing, Int64}}
   vals::Tuple{Any}
@@ -789,7 +789,7 @@ Body::Number
 │   %7  = Base.broadcasted(ITensors.val, ivs)::Base.Broadcast.Broadcasted{Base.Broadcast.Style{Tuple},Nothing,typeof(val),Tuple{Tuple{Pair{Index{Int64},Int64}}}}
 │   %8  = Base.materialize(%7)::Tuple{Int64}
 │         (vals = (%6)(%8, p))
-│   %10 = Core.tuple(T)::Tuple{ITensor{1}}
+│   %10 = Core.tuple(T)::Tuple{ITensor}
 │   %11 = Core._apply_iterate(Base.iterate, Base.getindex, %10, vals)::Number
 │   %12 = Core.typeassert(%11, ITensors.Number)::Number
 └──       return %12

docs/src/ITensorType.md

@@ -53,17 +53,17 @@ delta(::Type{<:Number}, ::QN, ::ITensors.Indices)
 ## Convert to Array
 
 ```@docs
-Array{ElT, N}(::ITensor{N}, ::Vararg{Index, N}) where {ElT, N}
+Array{ElT, N}(::ITensor, ::Vararg{Index, N}) where {ElT, N}
 array(::ITensor)
-matrix(::ITensor{2})
-vector(::ITensor{1})
+matrix(::ITensor)
+vector(::ITensor)
 ```
 
 ## Getting and setting elements
 
 ```@docs
 getindex(::ITensor, ::Any...)
-getindex(::ITensor{N}, ::Vararg{Int,N}) where {N}
+getindex(::ITensor, ::Vararg{Int,N}) where {N}
 setindex!(::ITensor, ::Number, ::Any...)
 setindex!(::ITensor, ::Number, ::Int...)
 ```

docs/src/index.md

@@ -299,7 +299,7 @@ It originates in physics with the purpose of finding
 eigenvectors of Hamiltonian (energy) matrices which model
 the behavior of quantum systems.
 
-```jldoctest; output=false, filter=[r"After sweep [1-5] energy=\-[0-9]{3}\.[0-9]{10,16} maxlinkdim=[0-9]{1,3} time=[0-9]{1,2}\.[0-9]{3}", r"Final energy = \-138\.[0-9]{10,16}"]
+```jldoctest; output=false, filter=[r"After sweep [1-5] energy=\-[0-9]{3}\.[0-9]{10,16} maxlinkdim=[0-9]{1,3} maxerr=[0-9]{1,2}\.[0-9]{1,3}E\-[0-9]{1,2} time=[0-9]{1,2}\.[0-9]{3}", r"Final energy = \-138\.[0-9]{10,16}"]
 using ITensors
 let
   # Create 100 spin-one indices
@@ -347,11 +347,10 @@ sweeps = Sweeps
 4 cutoff=1.0E-10, maxdim=100, mindim=1, noise=0.0E+00
 5 cutoff=1.0E-10, maxdim=200, mindim=1, noise=0.0E+00
 
-After sweep 1 energy=-137.845841178879 maxlinkdim=9 time=8.538
-After sweep 2 energy=-138.935378608196 maxlinkdim=20 time=0.316
-After sweep 3 energy=-138.940079710492 maxlinkdim=88 time=1.904
-After sweep 4 energy=-138.940086018149 maxlinkdim=100 time=4.179
-After sweep 5 energy=-138.940086075413 maxlinkdim=96 time=4.184
-Final energy = -138.94008607296038
+After sweep 1 energy=-137.954199761732 maxlinkdim=9 maxerr=2.43E-16 time=9.356
+After sweep 2 energy=-138.935058943878 maxlinkdim=20 maxerr=4.97E-06 time=0.671
+After sweep 3 energy=-138.940080155429 maxlinkdim=92 maxerr=1.00E-10 time=4.522
+After sweep 4 energy=-138.940086009318 maxlinkdim=100 maxerr=1.05E-10 time=11.644
+After sweep 5 energy=-138.940086058840 maxlinkdim=96 maxerr=1.00E-10 time=12.771
+Final energy = -138.94008605883985
 ```
-

src/ITensors.jl

@@ -140,7 +140,7 @@ end
 # (generated from precompile/make_precompile.jl
 # using SnoopCompile.jl)
 #
-include("../precompile/precompile.jl")
-_precompile_()
+#include("../precompile/precompile.jl")
+#_precompile_()
 
 end # module ITensors

src/decomp.jl

@@ -1,14 +1,14 @@
 
 """
-    TruncSVD{N}
+    TruncSVD
 
 ITensor factorization type for a truncated singular-value 
 decomposition, returned by `svd`.
 """
-struct TruncSVD{N1,N2}
-  U::ITensor{N1}
-  S::ITensor{2}
-  V::ITensor{N2}
+struct TruncSVD
+  U::ITensor
+  S::ITensor
+  V::ITensor
   spec::Spectrum
   u::Index
   v::Index
@@ -126,15 +126,15 @@ end
 
 
 """
-    TruncEigen{N}
+    TruncEigen
 
 ITensor factorization type for a truncated eigenvalue 
 decomposition, returned by `eigen`.
 """
-struct TruncEigen{N}
-  D::ITensor{2}
-  V::ITensor{N}
-  Vt::ITensor{N}
+struct TruncEigen
+  D::ITensor
+  V::ITensor
+  Vt::ITensor
   spec::Spectrum
   l::Index
   r::Index
@@ -148,17 +148,18 @@ iterate(E::TruncEigen, ::Val{:l}) = (E.l, Val(:r))
 iterate(E::TruncEigen, ::Val{:r}) = (E.r, Val(:done))
 iterate(E::TruncEigen, ::Val{:done}) = nothing
 
-function eigen(A::ITensor{N}, Linds, Rinds; kwargs...) where {N}
+function eigen(A::ITensor, Linds, Rinds; kwargs...)
   @debug_check begin
     if hasqns(A)
       @assert flux(A) == QN()
     end
   end
 
-  NL = length(Linds)
-  NR = length(Rinds)
-  NL != NR && error("Must have equal number of left and right indices")
-  N != NL + NR && error("Number of left and right indices must add up to total number of indices")
+  N   = ndims(A)
+  NL  = length(Linds)
+  NR  = length(Rinds)
+  NL != NR      && error("Must have equal number of left and right indices")
+  N  != NL + NR && error("Number of left and right indices must add up to total number of indices")
 
   ishermitian::Bool = get(kwargs, :ishermitian, false)