标签：pre -- span div blog logs mysql class mysq
ATAN(x) 用于返回 x 的反正切，即正切为 x 的值
mysql> SELECT ATAN(0.30933624960962325), ATAN(1); +---------------------------+--------------------+ | ATAN(0.30933624960962325) | ATAN(1) | +---------------------------+--------------------+ | 0.3 | 0.7853981633974483 | +---------------------------+--------------------+
标签：pre -- span div blog logs mysql class mysq
原文地址：http://www.cnblogs.com/pzk7788/p/6891926.html
