int ldegree(const symbol & s) const;
ex coeff(const symbol & s, int n = 1) const;
ex eval(int level = 0) const;
- ex series(const symbol & s, const ex & point, int order) const;
+ ex series(const relational & s, int order) const;
ex normal(lst &sym_lst, lst &repl_lst, int level=0) const;
ex subs(const lst & ls, const lst & lr) const;
protected: