Some fundamental methods in mathematical analysis are applied to prove the unique decomposition theorem : the distance between vector - valued pseudo almost periodic functions in metric spaces and almost periodic functions is an ergodic perturbation 应用数学分析中的基本方法证明了唯一分解定理，即距离空间中的向量值伪概周期函数和概周期函数之间的距离是一个遍历扰动。
