Conversion between set representations
This section of the manual lists the conversion functions between set representations.
Base.convert — Method.convert(::Type{HPOLYGON1},
        P::HPOLYGON2) where {HPOLYGON1<:AbstractHPolygon,
                             HPOLYGON2<:AbstractHPolygon}Convert between polygon types in H-representation.
Input
type– target typeP– source polygon
Output
The polygon represented as the target type.
Notes
We need the Union type for HPOLYGON1 because the target type must be concrete.
Base.convert — Method.convert(T::Type{HPOLYGON}, P::VPolygon) where {HPOLYGON<:AbstractHPolygon}Converts a polygon in vertex representation to a polygon in constraint representation.
Input
HPOLYGON– type used for dispatchP– polygon in vertex representation
Output
A polygon in constraint representation.
Base.convert — Method.convert(::Type{Hyperrectangle}, x::Interval)Converts a unidimensional interval into a hyperrectangle.
Input
Hyperrectangle– hyperrectangle type, used for dispatchx– interval
Output
A hyperrectangle.
Examples
julia> convert(Hyperrectangle, Interval(0.0, 1.0))
Hyperrectangle{Float64}([0.5], [0.5])Base.convert — Method.convert(::Type{Interval}, H::AbstractHyperrectangle)Converts a hyperrectangular set to a unidimensional interval.
Input
Interval– interval type, used for dispatchH– hyperrectangular set
Output
An interval.
Examples
julia> convert(Interval, Hyperrectangle{Float64}([0.5], [0.5]))
Interval{Float64,IntervalArithmetic.Interval{Float64}}([0, 1])Base.convert — Method.convert(::Type{Interval}, S::LazySet{N}) where {N<:Real}Converts a convex set to a unidimensional interval.
Input
Interval– interval type, used for dispatchS– convex set
Output
An interval.
Base.convert — Method.convert(::Type{Hyperrectangle},
        cpa::CartesianProductArray{N, HN}) where {N<:Real, HN<:AbstractHyperrectangle{N}}Converts the cartesian product of a finite number of hyperrectangular sets to a single hyperrectangle.
Input
Hyperrectangle– type used for dispatchS– cartesian product array of hyperrectangular set
Output
A hyperrectangle.
Algorithm
This implementation uses the center and radius_hyperrectangle methods of AbstractHyperrectangle.
Base.convert — Method.convert(::Type{Hyperrectangle},
        cpa::CartesianProductArray{N, Interval{N}}) where {N<:Real}Converts the cartesian product of a finite number of intervals to a single hyperrectangle.
Input
Hyperrectangle– type used for dispatchS– cartesian product array of intervals
Output
A hyperrectangle.
Algorithm
This implementation uses the min and max methods of Interval to reduce the allocatons and improve performance (see LazySets#1143).
Base.convert — Method.convert(::Type{HPOLYGON}, H::AbstractHyperrectangle) where
    {HPOLYGON<:AbstractHPolygon}Converts a hyperrectangular set to a polygon in constraint representation.
Input
HPOLYGON– type used for dispatchH– hyperrectangular set
Output
A polygon in constraint representation.
Base.convert — Method.convert(::Type{HPOLYGON}, P::HPolytope{N}) where
    {N<:Real, HPOLYGON<:AbstractHPolygon}Convert from 2D polytope in H-representation to polygon in H-representation.
Input
type– target typeP– source polytope (must be 2D)
Output
The 2D polytope represented as polygon.
Base.convert — Method.convert(::Type{HPOLYGON}, S::AbstractSingleton{N}
       ) where {N<:Real, HPOLYGON<:AbstractHPolygon}Convert from singleton to polygon in H-representation.
Input
type– target typeS– singleton
Output
A polygon in constraint representation with the minimal number of constraints (three).
Base.convert — Method.convert(::Type{HPOLYGON}, L::LineSegment{N}
      ) where {N<:Real, HPOLYGON<:AbstractHPolygon}Convert from line segment to polygon in H-representation.
Input
type– target typeL– line segment
Output
A flat polygon in constraint representation with the minimal number of constraints (four).
Base.convert — Method.convert(::Type{HPolyhedron}, P::AbstractPolytope)Convert a polytopic set to a polyhedron in H-representation.
Input
type– target typeP– source polytope
Output
The given polytope represented as a polyhedron in constraint representation.
Base.convert — Method.convert(::Type{HPolytope}, P::AbstractHPolygon)Convert from polygon in H-representation to polytope in H-representation.
Input
type– target typeP– source polygon
Output
The polygon represented as 2D polytope.
Base.convert — Method.convert(::Type{HPolytope}, H::AbstractHyperrectangle)Converts a hyperrectangular set to a polytope in constraint representation.
Input
HPolytope– type used for dispatchH– hyperrectangular set
Output
A polytope in constraint representation.
Base.convert — Method.convert(::Type{HPolytope}, P::AbstractPolytope)Convert a polytopic set to a polytope in H-representation.
Input
type– target typeP– source polytope
Output
The given polytope represented as a polytope in constraint representation.
Algorithm
First the list of constraints of P is computed, then the corresponding HPolytope is created.
Base.convert — Method.convert(::Type{HPolytope}, P::VPolytope)Convert from polytope in V-representation to polytope in H-representation.
Input
type– target typeP– source polytope
Output
The polytope in the dual representation.
Algorithm
The tohrep function is invoked. It requires the Polyhedra package.
Base.convert — Method.convert(::Type{VPolygon}, P::AbstractHPolygon)Converts a polygon in constraint representation to a polygon in vertex representation.
Input
VPolygon– type used for dispatchP– polygon in constraint representation
Output
A polygon in vertex representation.
Base.convert — Method.convert(::Type{VPolygon}, P::AbstractPolytope)Convert polytopic set to polygon in V-representation.
Input
type– target typeP– source polytope
Output
The 2D polytope represented as a polygon.
Base.convert — Method.convert(::Type{VPolytope}, P::AbstractPolytope)Convert polytopic type to polytope in V-representation.
Input
type– target typeP– source polytope
Output
The set P represented as a VPolytope.
Base.convert — Method.convert(::Type{VPolytope}, P::HPolytope)Convert from polytope in H-representation to polytope in V-representation.
Input
type– target typeP– source polytope
Output
The polytope in the dual representation.
Algorithm
The tovrep function is invoked. It requires the Polyhedra package.
Base.convert — Method.convert(::Type{Zonotope}, H::AbstractHyperrectangle)Converts a hyperrectangular set to a zonotope.
Input
ZonotopeH– hyperrectangular set
Output
A zonotope.