some cleanup for v0.14 (#191)

* some cleanup for v0.14

* try to remove some constprop macros

* bump version

* restore constprop

* remove unused compat entry

---------

Co-authored-by: Lukas Devos <ldevos98@gmail.com>

Author: Jutho

Changelog.md

@@ -17,6 +17,23 @@ Features that are planned to be implemented before the release of v1.0.0, in no
 
 ## v0.14
 
+### Use `DiagonalTensorMap` for singular values and eigenvalues
+
+The diagonal (1,1) tensor that contains the singular values or eigenvalues of a tensor
+are now explicitly represented as `DiagonalTensorMap` instances.
+
+### New index functionality
+There are is new functionality for manipulating the spaces associated with a tensor:
+* `flip(t, i)` changes the duality flag of the `i`th index of `t`, in such a way that flipping
+  a pair of contracted indices in an `@tensor` contraction does not affect the result.
+* `insertleftunit(t, i)` and `insertrightunit(t, i)` insert a trivial unit space to the left
+  or to right of index `i`, whereas `removeunit(t, i)` removes such a trivial unit space.
+
+### SVD truncation change (breaking)
+There is a subtle but breaking change in the truncation mechanism in SVD, where now it is
+guaranteed that smaller singular values are removed first, irrespective of the (quantum)
+dimension of the sector to which they belong
+
 ### `DiagonalTensorMap` and `reduceddim`
 
 This adds a `DiagonalTensorMap` type for representing tensor maps in which all of the

Project.toml

@@ -1,7 +1,7 @@
 name = "TensorKit"
 uuid = "07d1fe3e-3e46-537d-9eac-e9e13d0d4cec"
 authors = ["Jutho Haegeman"]
-version = "0.13.2"
+version = "0.14"
 
 [deps]
 LRUCache = "8ac3fa9e-de4c-5943-b1dc-09c6b5f20637"

docs/src/lib/spaces.md

@@ -112,6 +112,7 @@ There are also specific methods for `HomSpace` instances, that are used in deter
 the resuling `HomSpace` after applying certain tensor operations.
 
 ```@docs
+flip(W::HomSpace{S}, I) where {S}
 TensorKit.permute(::HomSpace{S}, ::Index2Tuple{N₁,N₂}) where {S,N₁,N₂}
 TensorKit.select(::HomSpace{S}, ::Index2Tuple{N₁,N₂}) where {S,N₁,N₂}
 TensorKit.compose(::HomSpace{S}, ::HomSpace{S}) where {S}

docs/src/lib/tensors.md

@@ -174,6 +174,7 @@ permute(::AbstractTensorMap, ::Index2Tuple{N₁,N₂}; ::Bool) where {N₁,N₂}
 braid(::AbstractTensorMap, ::Index2Tuple, ::IndexTuple; ::Bool)
 transpose(::AbstractTensorMap, ::Index2Tuple; ::Bool)
 repartition(::AbstractTensorMap, ::Int, ::Int; ::Bool)
+flip(t::AbstractTensorMap, I)
 twist(::AbstractTensorMap, ::Int; ::Bool)
 insertleftunit(::AbstractTensorMap, ::Int)
 insertrightunit(::AbstractTensorMap, ::Int)

src/TensorKit.jl

@@ -107,7 +107,8 @@ import TensorKitSectors: dim, BraidingStyle, FusionStyle, ⊠, ⊗
 import TensorKitSectors: dual, type_repr
 import TensorKitSectors: twist
 
-using Base: @boundscheck, @propagate_inbounds, OneTo, tail, front,
+using Base: @boundscheck, @propagate_inbounds, @constprop,
+            OneTo, tail, front,
             tuple_type_head, tuple_type_tail, tuple_type_cons,
             SizeUnknown, HasLength, HasShape, IsInfinite, EltypeUnknown, HasEltype
 using Base.Iterators: product, filter

src/auxiliary/auxiliary.jl

@@ -44,15 +44,6 @@ end
 @noinline _boundserror(P, i) = throw(BoundsError(P, i))
 @noinline _nontrivialspaceerror(P, i) = throw(ArgumentError(lazy"Attempting to remove a non-trivial space $(P[i])"))
 
-# Compat implementation:
-@static if VERSION < v"1.7"
-    macro constprop(setting, ex)
-        return esc(ex)
-    end
-else
-    using Base: @constprop
-end
-
 const VecOrNumber{T<:Number} = Union{DenseVector{T},T}
 
 """

src/tensors/indexmanipulations.jl

@@ -303,9 +303,9 @@ If `copy=false`, `tdst` might share data with `tsrc` whenever possible. Otherwis
 
 See also [`insertrightunit`](@ref) and [`removeunit`](@ref).
 """
-@constprop :aggressive function insertleftunit(t::AbstractTensorMap,
-                                               i::Int=numind(t) + 1; copy::Bool=true,
-                                               conj::Bool=false, dual::Bool=false)
+@constprop :aggressive function insertleftunit(t::AbstractTensorMap, i::Int=numind(t) + 1;
+                                               copy::Bool=true, conj::Bool=false,
+                                               dual::Bool=false)
     W = insertleftunit(space(t), i; conj, dual)
     tdst = similar(t, W)
     for (c, b) in blocks(t)
@@ -314,8 +314,8 @@ See also [`insertrightunit`](@ref) and [`removeunit`](@ref).
     return tdst
 end
 @constprop :aggressive function insertleftunit(t::TensorMap, i::Int=numind(t) + 1;
-                                               copy::Bool=false,
-                                               conj::Bool=false, dual::Bool=false)
+                                               copy::Bool=false, conj::Bool=false,
+                                               dual::Bool=false)
     W = insertleftunit(space(t), i; conj, dual)
     return TensorMap{scalartype(t)}(copy ? Base.copy(t.data) : t.data, W)
 end
@@ -360,8 +360,7 @@ This operation undoes the work of [`insertunit`](@ref).
     W = removeunit(space(t), i)
     return TensorMap{scalartype(t)}(copy ? Base.copy(t.data) : t.data, W)
 end
-@constprop :aggressive function removeunit(t::AbstractTensorMap, i::Int;
-                                           copy::Bool=true)
+@constprop :aggressive function removeunit(t::AbstractTensorMap, i::Int; copy::Bool=true)
     W = removeunit(space(t), i)
     tdst = similar(t, W)
     for (c, b) in blocks(t)

src/tensors/vectorinterface.jl

@@ -102,8 +102,25 @@ function VectorInterface.inner(tx::AbstractTensorMap, ty::AbstractTensorMap)
     InnerProductStyle(tx) === EuclideanInnerProduct() || throw_invalid_innerproduct(:inner)
     T = VectorInterface.promote_inner(tx, ty)
     s = zero(T)
-    for c in blocksectors(tx)
-        s += convert(T, dim(c)) * inner(block(tx, c), block(ty, c))
+    for ((cx, bx), (cy, by)) in zip(blocks(tx), blocks(ty))
+        s += convert(T, dim(cx)) * inner(bx, by)
     end
     return s
 end
+function VectorInterface.inner(tx::TensorMap, ty::TensorMap)
+    space(tx) == space(ty) || throw(SpaceMismatch("$(space(tx)) ≠ $(space(ty))"))
+    InnerProductStyle(tx) === EuclideanInnerProduct() || throw_invalid_innerproduct(:inner)
+    if FusionStyle(sectortype(tx)) isa UniqueFusion # all quantum dimensions are one
+        return inner(tx.data, ty.data)
+    else
+        T = VectorInterface.promote_inner(tx, ty)
+        s = zero(T)
+        for c in blocksectors(tx)
+            bx = parent(block(tx, c)) # matrix structure (reshape) does not matter
+            by = parent(block(ty, c)) # but does lead to slower path in inner
+            s += convert(T, dim(c)) * inner(bx, by)
+        end
+    end
+    return s
+end
+# TODO: do we need a fast path for `AdjointTensorMap` instances?