通过构造有单位元的环的主同余公式,给出了有单位元的环的主同余刻画;归纳于有单位元的环的一元项的形成和主同余公式的长度,从而给出有单位元的交换环和单位元的环的主同余的判定条件.
An equivalent characterization for principal congruence on ring with identity is obtained by constructing principal congruence formula on it.Then decision conditions for principal congruence on commutative ring with identity and ring with identity are given by inducing term and the length of the principal congruence formula of them.