These observations allow one to formalize the definition of reflection: a reflection is an involutive isometry of an Euclidean space whose set of fixed points is an affine subspace of codimension 1.
这些观察允许我们形式化反射的定义: 反射是欧几里得空间的对合等距,
的不动
集合是
为 1 的仿射子空间。