in a multigraph both multiple edges and multiple loops are allowed; a loop is a special edge . 在重图中允许有重边和重自环,自环是一种特殊的边。
multiple edges are allowed but loops are not without special notes 若无特殊说明,可以有重边。
about feature extraction, a new method of image edge detection, using multiple edge features and fuzzy reasoning, is submitted 在边缘检测技术的研究方面,本文提出一种新的边缘特征检测方法。