@@ -65,7 +65,7 @@ the section on [topological data of a fusion category](@ref ss_topologicalfusion
6565fusion and splitting trees that take the distinction between irreps and their conjugates
6666into account. Hence, in the previous example, if e.g. the first and third space in the
6767codomain and the second space in the domain of the tensor were dual spaces, the actual pair
68- of splitting and fusion tree would look as
68+ of splitting and fusion tree would look like
6969
7070![ extended double fusion tree] ( img/tree-extended.svg )
7171
@@ -80,12 +80,12 @@ We represent splitting trees and their adjoints using a specific immutable type
8080` FusionTree ` (which actually represents a splitting tree, but fusion tree is a more common
8181term), defined as
8282``` julia
83- struct FusionTree{I<: Sector ,N,M,L,T }
83+ struct FusionTree{I<: Sector ,N,M,L}
8484 uncoupled:: NTuple{N,I}
8585 coupled:: I
8686 isdual:: NTuple{N,Bool}
8787 innerlines:: NTuple{M,I} # fixed to M = N-2
88- vertices:: NTuple{L,T } # fixed to L = N-1
88+ vertices:: NTuple{L,Int } # fixed to L = N-1
8989end
9090```
9191Here, the fields are probably self-explanotary. The ` isdual ` field indicates whether an
@@ -96,8 +96,7 @@ isomorphism is present (if the corresponding value is `true`) or not. Note that
9696capabilities, such as checking for equality with ` == ` and support for
9797` hash(f::FusionTree, h::UInt) ` , as splitting and fusion trees are used as keys in look-up
9898tables (i.e. ` AbstractDictionary ` instances) to look up certain parts of the data of a
99- tensor. The type of ` L ` of the vertex labels can be ` Nothing ` when they are not needed
100- (i.e. if ` FusionStyle(I) isa MultiplicityFreeFusion ` ).
99+ tensor.
101100
102101` FusionTree ` instances are not checked for consistency (i.e. valid fusion rules etc) upon
103102creation, hence, they are assumed to be created correctly. The most natural way to create
@@ -146,7 +145,7 @@ TensorKit.jl, nor do they overload similarly named methods from Julia Base (see
146145
147146The first operation we discuss is an elementary braid of two neighbouring sectors
148147(indices), i.e. a so-called Artin braid or Artin generator of the braid group. Because
149- these two sectors do not appear on the same fusion vertex, some recoupling is necessary.
148+ these two sectors do not necessarily appear on the same fusion vertex, some recoupling is necessary.
150149The following represents two different ways to compute the result of such a braid as a
151150linear combination of new fusion trees in canonical order:
152151
@@ -263,13 +262,13 @@ that we need is summarized in
263262We will only need the B-symbol and not the A-symbol. Applying the left evaluation on the
264263second sector of a splitting tensor thus yields a linear combination of fusion tensors
265264(when ` FusionStyle(I) == GenericFusion() ` , or just a scalar times the corresponding
266- fusion tensor otherwise), with corresponding `` Z `` ismorphism . Taking the adjoint of this
265+ fusion tensor otherwise), with corresponding `` Z `` isomorphism . Taking the adjoint of this
267266relation yields the required relation to transform a fusion tensor into a splitting tensor
268267with an added `` Z^† `` isomorphism.
269268
270269However, we have to be careful if we bend a line on which a `` Z `` isomorphism (or its
271270adjoint) is already present. Indeed, it is exactly for this operation that we explicitly
272- need to take the presence of these isomorphisms into account. Indeed, we obtain the relation
271+ need to take the presence of these isomorphisms into account, obtaining the relation
273272
274273![ dual line bending] ( img/tree-linebending2.svg )
275274
@@ -334,7 +333,7 @@ given by
334333
335334The ` braid ` and ` permute ` routines for double fusion trees will be the main access point for
336335corresponding manipulations on tensors. As a consequence, results from this routine are
337- memoized, i.e. they are stored in some package wide 'least-recently used' cache (from
336+ memoized, i.e. they are stored in some package- wide 'least-recently used' cache (from
338337[ LRUCache.jl] ( https://github.com/JuliaCollections/LRUCache.jl ) ) that can be accessed as
339338` TensorKit.braidcache ` . By default, this cache stores up to ` 10^5 ` different ` braid ` or
340339` permute ` resuls, where one result corresponds to one particular combination of `(f1, f2,
@@ -360,7 +359,7 @@ a tensor, i.e. a morphism in the category `Vect` (this essentially coincides wit
360359of group representations), this explicit representation can be created, which can be useful
361360for checking purposes. Hereto, it is necessary that the * splitting tensor*
362361`` X^{ab}_{c,μ} `` , i.e. the Clebsch-Gordan coefficients of the group, are encoded via the
363- routine ` fusiontensor(a,b,c [,μ = nothing ]) ` , where the last argument is only necessary in
362+ routine ` fusiontensor(a,b,c [,μ = 1 ]) ` , where the last argument is only necessary in
364363the case of ` FusionStyle(I) == GenericFusion() ` . We can then convert a
365364` FusionTree{I,N} ` into an ` Array ` , which will yield a rank ` N+1 ` array where the first ` N `
366365dimensions correspond to the uncoupled sectors, and the last dimension to the coupled
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