moved orbit-related stuff to PropertyT package
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232
Orb_AutFN.jl
232
Orb_AutFN.jl
@ -1,232 +0,0 @@
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using JLD
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using JuMP
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using SCS
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using GroupRings
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using PropertyT
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using ValidatedNumerics
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using ArgParse
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import Nemo: Group, GroupElem
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immutable Settings
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name::String
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N::Int
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G::Group
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S::Vector
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AutS::Group
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radius::Int
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solver::SCSSolver
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upper_bound::Float64
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tol::Float64
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end
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immutable OrbitData
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name::String
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Us::Vector
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Ps::Vector{Array{JuMP.Variable,2}}
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cnstr::Vector
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laplacian::Vector
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laplacianSq::Vector
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dims::Vector{Int}
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end
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include("OrbitDecomposition.jl")
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function sparsify{T}(U::Array{T}, eps=eps(T))
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n = rank(U)
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W = deepcopy(U)
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W[abs.(W) .< eps] = zero(T)
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if rank(W) != n
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warn("Sparsification would decrease the rank!")
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W = U
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end
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W = sparse(W)
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dropzeros!(W)
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return W
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end
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function sparsify!{T}(U::SparseMatrixCSC{T}, eps=eps(T))
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U[abs.(U) .< eps] = zero(T)
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dropzeros!(U)
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return U
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end
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sparsify{T}(U::SparseMatrixCSC{T}, eps=eps(T)) = sparsify!(deepcopy(U), eps)
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function init_model(Uπs)
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m = JuMP.Model();
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l = size(Uπs,1)
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P = Vector{Array{JuMP.Variable,2}}(l)
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for k in 1:l
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s = size(Uπs[k],2)
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P[k] = JuMP.@variable(m, [i=1:s, j=1:s])
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JuMP.@SDconstraint(m, P[k] >= 0.0)
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end
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JuMP.@variable(m, λ >= 0.0)
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JuMP.@objective(m, Max, λ)
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return m, P
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end
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function init_OrbitData(name::String)
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splap = load(joinpath(name, "delta.jld"), "Δ");
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pm = load(joinpath(name, "pm.jld"), "pm");
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cnstr = PropertyT.constraints_from_pm(pm);
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splap² = GroupRings.mul(splap, splap, pm);
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Uπs = load(joinpath(name, "U_pis.jld"), "Uπs");
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# Uπs = sparsify.(Uπs);
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#dimensions of the corresponding πs:
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dims = load(joinpath(name, "U_pis.jld"), "dims")
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m, P = init_model(Uπs);
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orbits = load(joinpath(name, "orbits.jld"), "orbits");
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n = size(Uπs[1],1)
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orb_spcnstrm = [orbit_constraint(cnstr[collect(orb)], n) for orb in orbits]
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orb_splap = orbit_spvector(splap, orbits)
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orb_splap² = orbit_spvector(splap², orbits)
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orbData = OrbitData(name, Uπs, P, orb_spcnstrm, orb_splap, orb_splap², dims);
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# orbData = OrbitData(name, Uπs, P, orb_spcnstrm, splap, splap², dims);
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return m, orbData
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end
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function transform(U::AbstractArray, V::AbstractArray; sparse=false)
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w = U'*V*U
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sparse && sparsify!(w)
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return w
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end
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A(data::OrbitData, π, t) = data.dims[π]*transform(data.Us[π], data.cnstr[t])
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function constrLHS(m::JuMP.Model, data::OrbitData, t)
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l = endof(data.Us)
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lhs = @expression(m, sum(vecdot(A(data, π, t), data.Ps[π]) for π in 1:l))
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return lhs
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end
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function addconstraints!(m::JuMP.Model, data::OrbitData, l::Int=length(data.laplacian); var::Symbol = :λ)
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λ = m[var]
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# orbits = load(joinpath(data.name, "orbits.jld"), "orbits");
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# locate(t, orb=orbits) = findfirst(x->t in x, orb)
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for t in 1:l
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d, d² = data.laplacian[t], data.laplacianSq[t]
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# lhs = constrLHS(m, data, locate(t))
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lhs = constrLHS(m, data, t)
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if lhs == zero(lhs)
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if d == 0 && d² == 0
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info("Detected empty constraint")
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continue
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else
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warn("Adding unsatisfiable constraint!")
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end
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end
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JuMP.@constraint(m, lhs == d² - λ*d)
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end
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end
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function create_SDP_problem(name::String; upper_bound=Inf)
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info(PropertyT.logger, "Loading orbit data....")
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t = @timed SDP_problem, orb_data = init_OrbitData(name);
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info(PropertyT.logger, PropertyT.timed_msg(t))
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if upper_bound < Inf
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λ = JuMP.getvariable(SDP_problem, :λ)
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JuMP.@constraint(SDP_problem, λ <= upper_bound)
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end
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info(PropertyT.logger, "Adding constraints... ")
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t = @timed addconstraints!(SDP_problem, orb_data)
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info(PropertyT.logger, PropertyT.timed_msg(t))
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return SDP_problem, orb_data
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end
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function λandP(m::JuMP.Model, data::OrbitData)
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varλ = m[:λ]
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varP = data.Ps
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λ, Ps = PropertyT.λandP(data.name, m, varλ, varP)
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return λ, Ps
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end
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function λandP(m::JuMP.Model, data::OrbitData, sett::Settings)
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info(PropertyT.logger, "Solving SDP problem...")
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λ, Ps = λandP(m, data)
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info(PropertyT.logger, "Reconstructing P...")
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mreps = matrix_reps(sett.G, sett.S, sett.AutS, sett.radius)
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recP = reconstruct_sol(mreps, data.Us, Ps, data.dims)
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fname = PropertyT.λSDPfilenames(data.name)[2]
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save(fname, "origP", Ps, "P", recP)
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return λ, recP
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end
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function init_orbit_data(logger, sett::Settings; radius=2)
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ex(fname) = isfile(joinpath(sett.name, fname))
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files_exists = ex.(["delta.jld", "pm.jld", "U_pis.jld", "orbits.jld"])
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if !all(files_exists)
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compute_orbit_data(logger, sett.name, sett.G, sett.S, sett.AutS, radius=radius)
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end
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return 0
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end
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function orbit_check_propertyT(logger, sett::Settings)
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init_orbit_data(logger, sett, radius=sett.radius)
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Δ = PropertyT.ΔandSDPconstraints(sett.name, sett.G)[1]
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fnames = PropertyT.λSDPfilenames(sett.name)
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if all(isfile.(fnames))
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λ, P = PropertyT.λandP(sett.name)
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else
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info(logger, "Creating SDP problem...")
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SDP_problem, orb_data = create_SDP_problem(sett.name, upper_bound=sett.upper_bound)
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JuMP.setsolver(SDP_problem, sett.solver)
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λ, P = λandP(SDP_problem, orb_data, sett)
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end
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info(logger, "λ = $λ")
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info(logger, "sum(P) = $(sum(P))")
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info(logger, "maximum(P) = $(maximum(P))")
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info(logger, "minimum(P) = $(minimum(P))")
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if λ > 0
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isapprox(eigvals(P), abs(eigvals(P)), atol=sett.tol) ||
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warn("The solution matrix doesn't seem to be positive definite!")
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# @assert P == Symmetric(P)
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Q = real(sqrtm(Symmetric(P)))
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sgap = PropertyT.check_distance_to_positive_cone(Δ, λ, Q, 2*sett.radius, tol=sett.tol, rational=false)
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if isa(sgap, Interval)
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sgap = sgap.lo
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end
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if sgap > 0
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info(logger, "λ ≥ $(Float64(trunc(sgap,12)))")
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Kazhdan_κ = PropertyT.Kazhdan_from_sgap(sgap, length(sett.S))
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Kazhdan_κ = Float64(trunc(Kazhdan_κ, 12))
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info(logger, "κ($(sett.name), S) ≥ $Kazhdan_κ: Group HAS property (T)!")
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return true
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else
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sgap = Float64(trunc(sgap, 12))
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info(logger, "λ($(sett.name), S) ≥ $sgap: Group may NOT HAVE property (T)!")
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return false
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end
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end
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info(logger, "κ($(sett.name), S) ≥ $λ < 0: Tells us nothing about property (T)")
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return false
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end
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@ -1,206 +0,0 @@
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push!(LOAD_PATH, "./")
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using Nemo
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using Groups
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using GroupRings
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using PropertyT
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import Nemo.elements
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using JLD
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include("Projections.jl")
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###############################################################################
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#
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# Iterator protocol for Nemo.FinField
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#
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###############################################################################
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type FFEltsIter{T<:Nemo.FinField}
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all::Int
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field::T
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function FFEltsIter(F::T)
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return new(Int(characteristic(F)^degree(F)), F)
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end
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end
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FFEltsIter{T<:Nemo.FinField}(F::T) = FFEltsIter{T}(F)
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import Base: start, next, done, eltype, length
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Base.start(A::FFEltsIter) = (zero(A.field), 0)
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Base.next(A::FFEltsIter, state) = next_ffelem(state...)
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Base.done(A::FFEltsIter, state) = state[2] >= A.all
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Base.eltype(::Type{FFEltsIter}) = elem_type(A.field)
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Base.length(A::FFEltsIter) = A.all
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function next_ffelem(f::Nemo.FinFieldElem, c::Int)
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if c == 0
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return (f, (f, 1))
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elseif c == 1
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f = one(parent(f))
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return (f, (f, 2))
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else
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f = gen(parent(f))*f
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return (f, (f, c+1))
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end
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end
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import Nemo.elements
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elements(F::Nemo.FinField) = FFEltsIter(F)
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###############################################################################
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#
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# Orbit stuff
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#
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###############################################################################
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function orbit_decomposition(G::Nemo.Group, E::Vector, rdict=GroupRings.reverse_dict(E))
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elts = collect(elements(G))
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tovisit = trues(E);
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orbits = Vector{Vector{Int}}()
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for i in 1:endof(E)
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if tovisit[i]
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orbit = Vector{Int}()
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a = E[i]
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for g in elts
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idx = rdict[g(a)]
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tovisit[idx] = false
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push!(orbit,idx)
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end
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push!(orbits, unique(orbit))
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end
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end
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return orbits
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end
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function orbit_spvector(vect::AbstractVector, orbits)
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orb_vector = spzeros(length(orbits))
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for (i,o) in enumerate(orbits)
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k = vect[collect(o)]
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val = k[1]
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@assert all(k .== val)
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orb_vector[i] = val
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end
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return orb_vector
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end
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function orbit_constraint(constraints::Vector{Vector{Vector{Int64}}}, n)
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result = spzeros(n,n)
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for cnstr in constraints
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for p in cnstr
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result[p[2], p[1]] += 1.0
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end
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end
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return 1/length(constraints)*result
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end
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###############################################################################
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#
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# Matrix- and C*-representations
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#
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###############################################################################
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function matrix_repr(g::GroupElem, E, E_dict)
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rep_matrix = spzeros(Int, length(E), length(E))
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for (i,e) in enumerate(E)
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j = E_dict[g(e)]
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rep_matrix[i,j] = 1
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end
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return rep_matrix
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end
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function matrix_reps{T<:GroupElem}(G::Nemo.Group, S::Vector{T}, AutS::Nemo.Group, radius::Int)
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Id = (isa(G, Nemo.Ring) ? one(G) : G())
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E2, _ = Groups.generate_balls(S, Id, radius=radius)
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Edict = GroupRings.reverse_dict(E2)
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mreps = Dict(g=>matrix_repr(g, E2, Edict) for g in elements(AutS))
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return mreps
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end
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function reconstruct_sol(mreps::Dict, Us::Vector, Ps::Vector, dims::Vector)
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recP = zeros(size(Us[1],1), size(Us[1],1))
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for g in keys(mreps)
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for π in 1:endof(Us)
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recP .+= dims[π] .* mreps[g]*transform(Us[π]', Ps[π])*mreps[inv(g)]
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end
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end
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recP .*= 1/length(collect(keys(mreps)))
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return recP
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end
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function Cstar_repr(x::GroupRingElem, mreps)
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k = collect(keys(mreps))[1]
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res = zeros(size(mreps[k])...)
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for g in parent(x).basis
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res .+= x[g]*mreps[g]
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end
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return res
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end
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function orthSVD(M::AbstractMatrix)
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M = full(M)
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fact = svdfact(M)
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singv = fact[:S]
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|
||||||
M_rank = sum(singv .> maximum(size(M))*eps(eltype(singv)))
|
|
||||||
return fact[:U][:,1:M_rank]
|
|
||||||
end
|
|
||||||
|
|
||||||
function compute_orbit_data{T<:GroupElem}(logger, name::String, G::Nemo.Group, S::Vector{T}, AutS; radius=2)
|
|
||||||
isdir(name) || mkdir(name)
|
|
||||||
|
|
||||||
info(logger, "Generating ball of radius $(2*radius)")
|
|
||||||
|
|
||||||
# TODO: Fix that by multiple dispatch?
|
|
||||||
Id = (isa(G, Nemo.Ring) ? one(G) : G())
|
|
||||||
|
|
||||||
@time E4, sizes = Groups.generate_balls(S, Id, radius=2*radius);
|
|
||||||
info(logger, "Balls of sizes $sizes.")
|
|
||||||
info(logger, "Reverse dict")
|
|
||||||
@time E_dict = GroupRings.reverse_dict(E4)
|
|
||||||
|
|
||||||
info(logger, "Product matrix")
|
|
||||||
@time pm = GroupRings.create_pm(E4, E_dict, sizes[radius], twisted=true)
|
|
||||||
RG = GroupRing(G, E4, E_dict, pm)
|
|
||||||
Δ = PropertyT.splaplacian(RG, S)
|
|
||||||
@assert GroupRings.augmentation(Δ) == 0
|
|
||||||
save(joinpath(name, "delta.jld"), "Δ", Δ.coeffs)
|
|
||||||
save(joinpath(name, "pm.jld"), "pm", pm)
|
|
||||||
|
|
||||||
info(logger, "Decomposing E into orbits of $(AutS)")
|
|
||||||
@time orbs = orbit_decomposition(AutS, E4, E_dict)
|
|
||||||
@assert sum(length(o) for o in orbs) == length(E4)
|
|
||||||
save(joinpath(name, "orbits.jld"), "orbits", orbs)
|
|
||||||
|
|
||||||
info(logger, "Action matrices")
|
|
||||||
E2 = E4[1:sizes[radius]]
|
|
||||||
@time AutS_mreps = Dict(g=>matrix_repr(g, E2, E_dict) for g in elements(AutS))
|
|
||||||
|
|
||||||
info(logger, "Projections")
|
|
||||||
@time AutS_mps = rankOne_projections(AutS);
|
|
||||||
|
|
||||||
@time π_E_projections = [Cstar_repr(p, AutS_mreps) for p in AutS_mps]
|
|
||||||
|
|
||||||
info(logger, "Uπs...")
|
|
||||||
@time Uπs = orthSVD.(π_E_projections)
|
|
||||||
|
|
||||||
multiplicities = size.(Uπs,2)
|
|
||||||
info(logger, "multiplicities = $multiplicities")
|
|
||||||
dimensions = [Int(p[AutS()]*Int(order(AutS))) for p in AutS_mps];
|
|
||||||
info(logger, "dimensions = $dimensions")
|
|
||||||
@assert dot(multiplicities, dimensions) == sizes[radius]
|
|
||||||
|
|
||||||
save(joinpath(name, "U_pis.jld"), "Uπs", Uπs, "dims", dimensions)
|
|
||||||
return 0
|
|
||||||
end
|
|
||||||
135
Projections.jl
135
Projections.jl
@ -1,135 +0,0 @@
|
|||||||
using DirectProducts
|
|
||||||
using WreathProducts
|
|
||||||
|
|
||||||
###############################################################################
|
|
||||||
#
|
|
||||||
# Characters of PermutationGroup
|
|
||||||
#
|
|
||||||
###############################################################################
|
|
||||||
|
|
||||||
function chars(G::PermutationGroup)
|
|
||||||
permtype_unsorted(σ::Nemo.perm) = [length(c) for c in cycles(σ)]
|
|
||||||
permtype(σ::Nemo.perm) = sort(permtype_unsorted(σ))
|
|
||||||
|
|
||||||
χ_id(σ::Nemo.perm) = 1
|
|
||||||
|
|
||||||
χ_sgn(σ::Nemo.perm) = (-1)^parity(σ)
|
|
||||||
|
|
||||||
function χ_reg(σ::Nemo.perm)
|
|
||||||
fixed_points = countnz([(x == y? 1 : 0) for (x,y) in enumerate(σ.d)])
|
|
||||||
return fixed_points - 1
|
|
||||||
end
|
|
||||||
|
|
||||||
χ_regsgn(σ::Nemo.perm) = (-1)^parity(σ)*χ_reg(σ)
|
|
||||||
|
|
||||||
function χ_regviaS3(σ::Nemo.perm)
|
|
||||||
@assert parent(σ).n == 4
|
|
||||||
t = permtype(σ)
|
|
||||||
if t == [1,1,1,1]
|
|
||||||
result = 2
|
|
||||||
elseif t == [2,2]
|
|
||||||
result = 2
|
|
||||||
elseif t == [1,3]
|
|
||||||
result = -1
|
|
||||||
else
|
|
||||||
result = 0
|
|
||||||
end
|
|
||||||
return result
|
|
||||||
end
|
|
||||||
|
|
||||||
chars = [χ_id, χ_sgn, χ_regviaS3, χ_reg, χ_regsgn]
|
|
||||||
|
|
||||||
if G.n == 1
|
|
||||||
return chars[1:1]
|
|
||||||
elseif G.n == 2
|
|
||||||
return chars[1:2]
|
|
||||||
elseif G.n == 3
|
|
||||||
return [chars[1:2]..., chars[4]]
|
|
||||||
elseif G.n == 4
|
|
||||||
return chars[1:5]
|
|
||||||
else
|
|
||||||
throw("Characters for $G unknown!")
|
|
||||||
end
|
|
||||||
end
|
|
||||||
|
|
||||||
###############################################################################
|
|
||||||
#
|
|
||||||
# Character of DirectProducts
|
|
||||||
#
|
|
||||||
###############################################################################
|
|
||||||
|
|
||||||
function epsilon(i, g::DirectProducts.DirectProductGroupElem)
|
|
||||||
return reduce(*, 1, ((-1)^isone(g.elts[j]) for j in 1:i))
|
|
||||||
end
|
|
||||||
|
|
||||||
###############################################################################
|
|
||||||
#
|
|
||||||
# Projections
|
|
||||||
#
|
|
||||||
###############################################################################
|
|
||||||
|
|
||||||
function central_projection(RG::GroupRing, char::Function, T::Type=Rational{Int})
|
|
||||||
result = RG(T)
|
|
||||||
for g in RG.basis
|
|
||||||
result[g] = char(inv(g))
|
|
||||||
end
|
|
||||||
return convert(T, char(RG.group())//Int(order(RG.group))*result)
|
|
||||||
end
|
|
||||||
|
|
||||||
function rankOne_projections(G::PermutationGroup, T::Type=Rational{Int})
|
|
||||||
RG = GroupRing(G)
|
|
||||||
projections = [central_projection(RG, χ, T) for χ in chars(G)]
|
|
||||||
|
|
||||||
if G.n == 1 || G.n == 2
|
|
||||||
return projections
|
|
||||||
elseif G.n == 3
|
|
||||||
rankone_projs = [
|
|
||||||
projections[1],
|
|
||||||
projections[2],
|
|
||||||
1//2*(one(RG) - RG(RG.group([2,1,3])))*projections[3]
|
|
||||||
]
|
|
||||||
return rankone_projs
|
|
||||||
elseif G.n == 4
|
|
||||||
rankone_projs = [
|
|
||||||
projections[1],
|
|
||||||
projections[2],
|
|
||||||
1//2*(one(RG) - RG(RG.group([2,1,3,4])))*projections[3],
|
|
||||||
1//2*(one(RG) - RG(RG.group([2,1,3,4])))*projections[4],
|
|
||||||
1//2*(one(RG) + RG(RG.group([2,1,3,4])))*projections[5]]
|
|
||||||
return rankone_projs
|
|
||||||
else
|
|
||||||
throw("Rank-one projections for $G unknown!")
|
|
||||||
end
|
|
||||||
end
|
|
||||||
|
|
||||||
function rankOne_projections(BN::WreathProducts.WreathProduct, T::Type=Rational{Int})
|
|
||||||
|
|
||||||
N = BN.P.n
|
|
||||||
# projections as elements of the group rings RSₙ
|
|
||||||
SNprojs_nc = [rankOne_projections(PermutationGroup(i), T) for i in 1:N]
|
|
||||||
|
|
||||||
# embedding into group ring of BN
|
|
||||||
RBN = GroupRing(BN)
|
|
||||||
RFFFF_projs = [central_projection(GroupRing(BN.N), g->epsilon(i,g), T)
|
|
||||||
for i in 0:BN.P.n]
|
|
||||||
Qs = [RBN(q, g -> BN(g)) for q in RFFFF_projs]
|
|
||||||
|
|
||||||
function incl(k::Int, g::perm, WP::WreathProduct=BN)
|
|
||||||
@assert length(g.d) + k <= WP.P.n
|
|
||||||
arr = [1:k; g.d .+ k; (length(g.d)+k+1):WP.P.n]
|
|
||||||
return WP(WP.P(arr))
|
|
||||||
end
|
|
||||||
|
|
||||||
all_projs=[Qs[1]*RBN(p, g-> incl(0,g)) for p in SNprojs_nc[N]]
|
|
||||||
|
|
||||||
for i in 1:N-1
|
|
||||||
Sk_first = [RBN(p, g->incl(0,g)) for p in SNprojs_nc[i]]
|
|
||||||
Sk_last = [RBN(p, g->incl(i,g)) for p in SNprojs_nc[N-i]]
|
|
||||||
append!(all_projs,
|
|
||||||
[Qs[i+1]*p1*p2 for (p1,p2) in Base.product(Sk_first,Sk_last)])
|
|
||||||
end
|
|
||||||
|
|
||||||
append!(all_projs, [Qs[N+1]*RBN(p, g-> incl(0,g)) for p in SNprojs_nc[N]])
|
|
||||||
|
|
||||||
return all_projs
|
|
||||||
end
|
|
||||||
Loading…
Reference in New Issue
Block a user