摘要
利用非扩张算子的不动点理论,证明了最佳逼近和不变逼近的存在性。所获结果推广改进了某些已知结果,并给出了A. Smolus问题的一个扩充性回答。
The existence for both best and invariant approximations is proven by using the fixed point theory of nonexpansive operators. The obtained results generalize and improve some known results, and also provide an extension answer to a question of A. Smolus.
关键词
非扩张算子
最佳逼近
不变逼近
non-expansive operator
best approximation
invariant approximation
