Custom collection types

type CacheIndexDict{K, KeyRange<:AbstractUnitRange{K}, V} <: RigidBodyDynamics.CustomCollections.AbstractIndexDict{K,V}

Like IndexDict, but contains an additional Bool dirty bit to be used in algorithms involving cached data.

struct ConstVector{T} <: AbstractArray{T,1}

An immutable AbstractVector for which all elements are the same, represented compactly and as an isbits type if the element type is isbits.

bitstype 64 DiscardVector <: AbstractArray{Any,1}

DiscardVector is an AbstractVector whose setindex! simply discards the value. This is useful for broadcast! calls where the output of the broadcasted function is not interesting, specifically when the broadcasted function is in-place and there are arguments that need to be treated as scalars, so that a simple foreach doesn't do the job.

struct IndexDict{K, KeyRange<:AbstractUnitRange{K}, V} <: RigidBodyDynamics.CustomCollections.AbstractIndexDict{K,V}

An associative type whose keys are an AbstractUnitRange, and whose values are stored in a Vector. IndexDict is an ordered associative collection, with the order determined by key range. The nature of the keys enables very fast lookups and stores.

Examples

julia> IndexDict(2 : 4, [4, 5, 6])
RigidBodyDynamics.CustomCollections.IndexDict{Int64,UnitRange{Int64},Int64} with 3 entries:
  2 => 4
  3 => 5
  4 => 6

julia> IndexDict{Int32, UnitRange{Int32}}(i => 3 * i for i in Int32[4, 2, 3])
RigidBodyDynamics.CustomCollections.IndexDict{Int32,UnitRange{Int32},Int64} with 3 entries:
  2 => 6
  3 => 9
  4 => 12

struct NullDict{K, V} <: Associative{K,V}

An immutable associative type that signifies an empty dictionary and does not allocate any memory.

struct SegmentedVector{K, T, KeyRange<:Range{K}, P<:AbstractArray{T,1}} <: AbstractArray{T,1}

SegmentedVector is an AbstractVector backed by another AbstractVector (its parent), which additionally stores an IndexDict containing views into the parent. Together, these views cover the parent.

Examples

julia> x = [1., 2., 3., 4.]
4-element Array{Float64,1}:
 1.0
 2.0
 3.0
 4.0

julia> viewlength(i) = 2
viewlength (generic function with 1 method)

julia> xseg = SegmentedVector{Int}(x, 1 : 2, viewlength)
4-element RigidBodyDynamics.CustomCollections.SegmentedVector{Int64,Float64,Base.OneTo{Int64},Array{Float64,1}}:
 1.0
 2.0
 3.0
 4.0

julia> segments(xseg)[1]
2-element SubArray{Float64,1,Array{Float64,1},Tuple{UnitRange{Int64}},true}:
 1.0
 2.0

julia> yseg = similar(xseg, Int32); yseg .= 1 : 4 # same view ranges, different element type
4-element RigidBodyDynamics.CustomCollections.SegmentedVector{Int64,Int32,Base.OneTo{Int64},Array{Int32,1}}:
 1
 2
 3
 4

julia> segments(yseg)[2]
2-element SubArray{Int32,1,Array{Int32,1},Tuple{UnitRange{Int64}},true}:
 3
 4