Add tools to compute in mapping class groups
This commit is contained in:
parent
e0d3cb607b
commit
ed12d87b7a
119
MCG.jl
119
MCG.jl
@ -27,7 +27,7 @@ function parse_commandline()
|
||||
"--radius"
|
||||
help = "Radius of ball B_r(e,S) to find solution over"
|
||||
arg_type = Int
|
||||
default = 4
|
||||
default = 2
|
||||
"--warmstart"
|
||||
help = "Use warmstart.jl as the initial guess for SCS"
|
||||
action = :store_true
|
||||
@ -38,113 +38,15 @@ end
|
||||
const PARSEDARGS = parse_commandline()
|
||||
|
||||
include("CPUselect.jl")
|
||||
# set_parallel_mthread(PARSEDARGS, workers=true)
|
||||
set_parallel_mthread(PARSEDARGS, workers=false)
|
||||
|
||||
include("FPGroups_GAP.jl")
|
||||
|
||||
module MCGrps
|
||||
|
||||
using Groups
|
||||
using Nemo
|
||||
|
||||
Comm(x,y) = x*y*x^-1*y^-1
|
||||
|
||||
function Group(N::Int)
|
||||
if N == 2
|
||||
MCGroup = Groups.FPGroup(["a1","a2","a3","a4","a5"]);
|
||||
S = Nemo.gens(MCGroup)
|
||||
|
||||
N = length(S)
|
||||
A = prod(reverse(S))*prod(S)
|
||||
|
||||
relations = [
|
||||
[Comm(S[i], S[j]) for i in 1:N for j in 1:N if abs(i-j) > 1]...,
|
||||
[S[i]*S[i+1]*S[i]*inv(S[i+1]*S[i]*S[i+1]) for i in 1:N-1]...,
|
||||
(S[1]*S[2]*S[3])^4*inv(S[5])^2,
|
||||
Comm(A, S[1]),
|
||||
A^2
|
||||
]
|
||||
|
||||
relations = [relations; [inv(rel) for rel in relations]]
|
||||
Groups.add_rels!(MCGroup, Dict(rel => MCGroup() for rel in relations))
|
||||
return MCGroup
|
||||
|
||||
elseif N < 2
|
||||
throw("Genus must be at least 2!")
|
||||
end
|
||||
|
||||
MCGroup = Groups.FPGroup(["a$i" for i in 0:2N])
|
||||
S = Nemo.gens(MCGroup)
|
||||
|
||||
a0 = S[1]
|
||||
A = S[2:end]
|
||||
k = length(A)
|
||||
|
||||
relations = [
|
||||
[Comm(A[i], A[j]) for i in 1:k for j in 1:k if abs(i-j) > 1]...,
|
||||
[Comm(a0, A[i]) for i in 1:k if i != 4]...,
|
||||
[A[i]*A[(i+1)]*A[i]*inv(A[i+1]*A[i]*A[i+1]) for i in 1:k-1]...,
|
||||
A[4]*a0*A[4]*inv(a0*A[4]*a0)
|
||||
]
|
||||
|
||||
# 3-chain relation
|
||||
c = prod(reverse(A[1:4]))*prod(A[1:4])
|
||||
b0 = c*a0*inv(c)
|
||||
push!(relations, (A[1]*A[2]*A[3])^4*inv(a0*b0))
|
||||
|
||||
# Lantern relation
|
||||
b1 = inv(A[4]*A[5]*A[3]*A[4])*a0*(A[4]*A[5]*A[3]*A[4])
|
||||
b2 = inv(A[2]*A[3]*A[1]*A[2])*b1*(A[2]*A[3]*A[1]*A[2])
|
||||
u = inv(A[6]*A[5])*b1*(A[6]*A[5])
|
||||
x = prod(reverse(A[2:6]))*u*prod(inv.(A[1:4]))
|
||||
b3 = x*a0*inv(x)
|
||||
push!(relations, a0*b2*b1*inv(A[1]*A[3]*A[5]*b3))
|
||||
|
||||
# Hyperelliptic relation
|
||||
X = prod(reverse(A))*prod(A)
|
||||
|
||||
function n(i::Int, b=b0)
|
||||
if i == 1
|
||||
return A[1]
|
||||
elseif i == 2
|
||||
return b
|
||||
else
|
||||
return w(i-2)*n(i-2)*w(i-2)
|
||||
end
|
||||
end
|
||||
|
||||
function w(i::Int)
|
||||
(A[2i+4]*A[2i+3]*A[2i+2]* n(i+1))*(A[2i+1]*A[2i] *A[2i+2]*A[2i+1])*
|
||||
(A[2i+3]*A[2i+2]*A[2i+4]*A[2i+3])*( n(i+1)*A[2i+2]*A[2i+1]*A[2i] )
|
||||
end
|
||||
|
||||
push!(relations, X*n(N)*inv(n(N)*X))
|
||||
|
||||
relations = [relations; [inv(rel) for rel in relations]]
|
||||
Groups.add_rels!(MCGroup, Dict(rel => MCGroup() for rel in relations))
|
||||
@show MCGroup
|
||||
return MCGroup
|
||||
end
|
||||
|
||||
###############################################################################
|
||||
#
|
||||
# Misc
|
||||
#
|
||||
###############################################################################
|
||||
|
||||
function groupname(parsed_args)
|
||||
N = parsed_args["N"]
|
||||
return groupname(N), N
|
||||
end
|
||||
|
||||
groupname(N::Int) = "MCG$(N)"
|
||||
|
||||
end #of module MCGrps
|
||||
|
||||
|
||||
|
||||
using SCS.SCSSolver
|
||||
using PropertyT
|
||||
using Groups
|
||||
|
||||
include("FPGroups_GAP.jl")
|
||||
include("groups/mappingclassgroup.jl")
|
||||
|
||||
function main(GROUP, parsed_args)
|
||||
|
||||
@ -157,12 +59,11 @@ function main(GROUP, parsed_args)
|
||||
name, N = GROUP.groupname(parsed_args)
|
||||
isdir(name) || mkdir(name)
|
||||
|
||||
G = GROUP.Group(N)
|
||||
S = Nemo.gens(G)
|
||||
G, S = GROUP.generatingset(N)
|
||||
relations = [k*inv(v) for (k,v) in G.rels]
|
||||
prepare_pm_delta(name, GAP_groupcode(S, relations), radius)
|
||||
|
||||
S = unique([S; [inv(s) for s in S]])
|
||||
S = unique([S; inv.(S)])
|
||||
|
||||
Id = G()
|
||||
|
||||
@ -178,10 +79,10 @@ function main(GROUP, parsed_args)
|
||||
info(logger, "Threads: $(Threads.nthreads())")
|
||||
info(logger, "Workers: $(workers())")
|
||||
|
||||
solver = SCSSolver(eps=tol, max_iters=iterations, linearsolver=SCS.Direct, alpha=1.9, acceleration_lookback=1)
|
||||
solver = SCSSolver(eps=tol, max_iters=iterations, linearsolver=SCS.Direct, alpha=1.95, acceleration_lookback=1)
|
||||
|
||||
PropertyT.check_property_T(name, S, Id, solver, upper_bound, tol, radius, warm)
|
||||
return 0
|
||||
end
|
||||
|
||||
main(MCGrps, PARSEDARGS)
|
||||
main(MappingClassGroups, PARSEDARGS)
|
||||
|
109
groups/mappingclassgroup.jl
Normal file
109
groups/mappingclassgroup.jl
Normal file
@ -0,0 +1,109 @@
|
||||
module MappingClassGroups
|
||||
|
||||
using Nemo
|
||||
using Groups
|
||||
|
||||
###############################################################################
|
||||
#
|
||||
# Generating set
|
||||
#
|
||||
###############################################################################
|
||||
|
||||
Comm(x,y) = x*y*x^-1*y^-1
|
||||
|
||||
function generatingset(N::Int)
|
||||
if N == 2
|
||||
MCGroup = Groups.FPGroup(["a1","a2","a3","a4","a5"]);
|
||||
S = Nemo.gens(MCGroup)
|
||||
|
||||
N = length(S)
|
||||
A = prod(reverse(S))*prod(S)
|
||||
|
||||
relations = [
|
||||
[Comm(S[i], S[j]) for i in 1:N for j in 1:N if abs(i-j) > 1]...,
|
||||
[S[i]*S[i+1]*S[i]*inv(S[i+1]*S[i]*S[i+1]) for i in 1:N-1]...,
|
||||
(S[1]*S[2]*S[3])^4*inv(S[5])^2,
|
||||
Comm(A, S[1]),
|
||||
A^2
|
||||
]
|
||||
|
||||
relations = [relations; [inv(rel) for rel in relations]]
|
||||
Groups.add_rels!(MCGroup, Dict(rel => MCGroup() for rel in relations))
|
||||
return MCGroup
|
||||
|
||||
elseif N < 2
|
||||
throw("Genus must be at least 2!")
|
||||
end
|
||||
|
||||
MCGroup = Groups.FPGroup(["a$i" for i in 0:2N])
|
||||
S = Nemo.gens(MCGroup)
|
||||
|
||||
a0 = S[1]
|
||||
A = S[2:end]
|
||||
k = length(A)
|
||||
|
||||
relations = [
|
||||
[Comm(A[i], A[j]) for i in 1:k for j in 1:k if abs(i-j) > 1]...,
|
||||
[Comm(a0, A[i]) for i in 1:k if i != 4]...,
|
||||
[A[i]*A[(i+1)]*A[i]*inv(A[i+1]*A[i]*A[i+1]) for i in 1:k-1]...,
|
||||
A[4]*a0*A[4]*inv(a0*A[4]*a0)
|
||||
]
|
||||
|
||||
# 3-chain relation
|
||||
c = prod(reverse(A[1:4]))*prod(A[1:4])
|
||||
b0 = c*a0*inv(c)
|
||||
push!(relations, (A[1]*A[2]*A[3])^4*inv(a0*b0))
|
||||
|
||||
# Lantern relation
|
||||
b1 = inv(A[4]*A[5]*A[3]*A[4])*a0*(A[4]*A[5]*A[3]*A[4])
|
||||
b2 = inv(A[2]*A[3]*A[1]*A[2])*b1*(A[2]*A[3]*A[1]*A[2])
|
||||
u = inv(A[6]*A[5])*b1*(A[6]*A[5])
|
||||
x = prod(reverse(A[2:6]))*u*prod(inv.(A[1:4]))
|
||||
b3 = x*a0*inv(x)
|
||||
push!(relations, a0*b2*b1*inv(A[1]*A[3]*A[5]*b3))
|
||||
|
||||
# Hyperelliptic relation
|
||||
X = prod(reverse(A))*prod(A)
|
||||
|
||||
function n(i::Int, b=b0)
|
||||
if i == 1
|
||||
return A[1]
|
||||
elseif i == 2
|
||||
return b
|
||||
else
|
||||
return w(i-2)*n(i-2)*w(i-2)
|
||||
end
|
||||
end
|
||||
|
||||
function w(i::Int)
|
||||
(A[2i+4]*A[2i+3]*A[2i+2]* n(i+1))*(A[2i+1]*A[2i] *A[2i+2]*A[2i+1])*
|
||||
(A[2i+3]*A[2i+2]*A[2i+4]*A[2i+3])*( n(i+1)*A[2i+2]*A[2i+1]*A[2i] )
|
||||
end
|
||||
|
||||
push!(relations, X*n(N)*inv(n(N)*X))
|
||||
|
||||
relations = [relations; [inv(rel) for rel in relations]]
|
||||
Groups.add_rels!(MCGroup, Dict(rel => MCGroup() for rel in relations))
|
||||
|
||||
return MCGroup, gens(MCGroup)
|
||||
end
|
||||
|
||||
function generatingset(parsed_args)
|
||||
N = parsed_args["N"]
|
||||
return generatingset(N)
|
||||
end
|
||||
|
||||
###############################################################################
|
||||
#
|
||||
# Misc
|
||||
#
|
||||
###############################################################################
|
||||
|
||||
function groupname(parsed_args)
|
||||
N = parsed_args["N"]
|
||||
return groupname(N), N
|
||||
end
|
||||
|
||||
groupname(N::Int) = "MCG$(N)"
|
||||
|
||||
end #of module MappingClassGroups
|
Loading…
Reference in New Issue
Block a user