function op_mat(op)
op = op[:as_poly](domain="C")
op_a = op.x[:gens]
nab = op[:length]()
op_ab = ones(SymPy.Sym, nab)
coef = zeros(Complex, nab)
mat = zeros(Int64, length(op_a), nab)
for (i, (ps, c)) in enumerate(op[:as_dict]())
    for (j, p) in enumerate(ps)
        mat[j, i] = p
        op_ab[i] = op_a[j]^p * op_ab[i]
    end
    coef[i] = c
end

return op_a, op_ab, mat, coef