1、欧式空间 Euclidean space
These are distances between points and the angles between lines or vectors, which satisfy certain conditions (see below), which makes a set of points a Euclidean space. The natural way to obtain these quantities is by introducing and using the standard inner product (also known as the dot product) on Rn. The inner product of any two real n-vectors x and y is defined by
where xi and yi are ith coordinates of vectors x and y respectively. The result is always a real number.
"However, the neural network architectures are not in Euclidean space" 神经网络结构不是欧式空间。