ulia> root_system([2 -1; -1 2])
Root system defined by Cartan matrix
  [ 2   -1]
  [-1    2]

julia> root_system(matrix(ZZ, 2, 2, [2, -1, -1, 2]))
Root system defined by Cartan matrix
  [ 2   -1]
  [-1    2]

julia> weyl_group([2 -1; -1 2])
ERROR: MethodError: no method matching weyl_group(::Matrix{Int64})
The function `weyl_group` exists, but no method is defined for this combination of argument types.

Closest candidates are:
  weyl_group(::Vector{Tuple{Symbol, Int64}})
   @ Oscar ~/.julia/packages/Oscar/5kSAT/experimental/LieAlgebras/src/WeylGroup.jl:39
  weyl_group(::Symbol, ::Int64)
   @ Oscar ~/.julia/packages/Oscar/5kSAT/experimental/LieAlgebras/src/WeylGroup.jl:30
  weyl_group(::ZZMatrix)
   @ Oscar ~/.julia/packages/Oscar/5kSAT/experimental/LieAlgebras/src/WeylGroup.jl:15
  ...

Stacktrace:
 [1] top-level scope
   @ REPL[6]:1

julia> weyl_group(matrix(ZZ, 2, 2, [2, -1, -1, 2]))
Weyl group for root system defined by Cartan matrix [2 -1; -1 2]

julia> Oscar.versioninfo(full=true)
OSCAR version 1.2.2
  combining:
    AbstractAlgebra.jl   v0.43.12
    GAP.jl               v0.12.3
    Hecke.jl             v0.34.9
    Nemo.jl              v0.47.5
    Polymake.jl          v0.11.24
    Singular.jl          v0.23.10
  building on:
    FLINT_jll               v300.100.301+0
    GAP_jll                 v400.1300.102+2
    Singular_jll            v404.0.711+0
    libpolymake_julia_jll   v0.13.0+0
    libsingular_julia_jll   v0.46.1+0
    polymake_jll            v400.1300.2+0
See `]st -m` for a full list of dependencies.

Julia Version 1.11.2
Commit 5e9a32e7af2 (2024-12-01 20:02 UTC)
Build Info:
  Official https://julialang.org/ release
Platform Info:
  OS: Linux (x86_64-linux-gnu)
  CPU: 12 × 12th Gen Intel(R) Core(TM) i5-12400
  WORD_SIZE: 64
  LLVM: libLLVM-16.0.6 (ORCJIT, alderlake)
Threads: 1 default, 0 interactive, 1 GC (on 12 virtual cores)
Official https://julialang.org/ release