1
0
mirror of https://github.com/kalmarek/Groups.jl.git synced 2024-10-15 07:20:35 +02:00

rewrite simplify_perms!

This commit is contained in:
kalmarek 2018-03-28 12:20:03 +02:00
parent 6b0499005f
commit f493ed7283

View File

@ -329,42 +329,40 @@ function getperm(s::AutSymbol)
end
end
function simplify_perms!(W::Automorphism)
function simplify_perms!(W::Automorphism{N}) where N
reduced = true
for i in 1:length(W.symbols) - 1
current = W.symbols[i]
if isa(current.typ, PermAut)
next_s = W.symbols[i+1]
if isa(next_s.typ, PermAut)
if current.pow != 1
current = perm_autsymbol(perm(current), pow=current.pow)
end
reduced = false
if next_s.pow != 1
next_s = perm_autsymbol(perm(next_s), pow=next_s.pow)
end
p1 = getperm(current)
p2 = getperm(next_s)
W.symbols[i] = id_autsymbol()
W.symbols[i+1] = perm_autsymbol(p1*p2)
to_delete = Int[]
for i in 1:length(W.symbols)-1
if isa(W.symbols[i].typ, PermAut) && isa(W.symbols[i+1].typ, PermAut)
reduced = false
c = W.symbols[i]
n = W.symbols[i+1]
p = (getperm(c)*getperm(n)).d
if p == PermutationGroup(N)()
push!(to_delete, i, i+1)
else
W.symbols[i+1].typ.perm.d = p
push!(to_delete, i)
end
end
end
deleteat!(W.symbols, find(x -> x.pow == 0, W.symbols))
deleteat!(W.symbols, to_delete)
return reduced
end
function reduce!(W::Automorphism)
if length(W) < 2
deleteat!(W.symbols, find(x -> x.pow == 0, W.symbols))
if length(W.symbols) == 0
return W
elseif length(W.symbols) == 1 && W.symbols[1].pow == 0
deleteat!(W.symbols, 1)
W.modified = true
else
reduced = false
while !reduced
reduced = simplify_perms!(W) && free_reduce!(W)
deleteat!(W.symbols, find(x -> x.pow == 0, W.symbols))
end
end
deleteat!(W.symbols, find(x -> x.pow == 0, W.symbols))
W.modified = true