AbstractBlockTensorMap{E,S,N₁,N₂}

Abstract supertype for tensor maps that have additional block structure, i.e. they act on vector spaces that have a direct sum structure. These behave like AbstractTensorMap but have additional methods to facilitate indexing and manipulation of the block structure.

struct BlockTensorMap{TT<:AbstractTensorMap{E,S,N₁,N₂}} <: AbstractTensorMap{E,S,N₁,N₂}

Dense BlockTensorMap type that stores tensors of type TT in a dense array.

struct SparseBlockTensorMap{TT<:AbstractTensorMap{E,S,N₁,N₂}} <: AbstractBlockTensorMap{E,S,N₁,N₂}

Sparse SparseBlockTensorMap type that stores tensors of type TT in a sparse dictionary.

struct SumSpace{S<:ElementarySpace} <: ElementarySpace

A (lazy) direct sum of elementary vector spaces of type S.

struct SumSpaceIndices{S,N₁,N₂} <: AbstractArray{TensorMapSpace{S,N₁,N₂},N₁ + N₂}

droptol!(t::AbstractBlockTensorMap, tol=eps(real(scalartype(t)))^(3/4))

Remove the tensor entries of a blocktensor that have norm ≤(tol).

dropzeros!(t::AbstractBlockTensorMap)

Remove the tensor entries of a blocktensor that have norm 0. Only applicable to sparse blocktensors.

eachspace(V::TensorMapSumSpace) -> SumSpaceIndices

Return an object that can be used to obtain the subspaces of a BlockTensorMap.

sprand([rng], T::Type, W::TensorMapSumSpace, p::Real)

Construct a sparse blocktensor with entries compatible with type T and space W. Each entry is nonzero with probability p.

spzeros(T::Type, W::TensorMapSumSpace)
spzeros(T, W, nonzero_inds)

Construct a sparse blocktensor with entries compatible with type T and space W. By default, the tensor will be empty, but nonzero entries can be specified by passing a tuple of indices nonzero_inds.

sumspacetype(::Union{S,Type{S}}) where {S<:ElementarySpace}

Return the type of a SumSpace with elements of type S.