public Dictionary <FermionTermType, Double> ComputeOneNorms()
 {
     return(FermionTerms.ToDictionary(
                (termTypePair) => termTypePair
                .Key,
                (termTypePair) => termTypePair
                .Value
                .AsParallel()
                .Select(o => Abs(o.coeff))
                .Sum()
                ));
 }