避免在R

Question

假设我们有这些对象：

distM_ref1_matrix <- dist(cbind(distM_ref1$x, distM_ref1$y))
distM_ref2_matrix <- dist(cbind(distM_ref2$x, distM_ref2$y))
distM_ref3_matrix <- dist(cbind(distM_ref3$x, distM_ref3$y))
distM_ref4_matrix <- dist(cbind(distM_ref4$x, distM_ref4$y))
distM_ref5_matrix <- dist(cbind(distM_ref5$x, distM_ref5$y))
distM_ref6_matrix <- dist(cbind(distM_ref6$x, distM_ref6$y))
distM_ref7_matrix <- dist(cbind(distM_ref7$x, distM_ref7$y))
distM_ref8_matrix <- dist(cbind(distM_ref8$x, distM_ref8$y))
distM_ref9_matrix <- dist(cbind(distM_ref9$x, distM_ref9$y))

我有两个问题：

1. 如何通过一行自动创建所有这些对象来保存代码？考虑我确实有大量的等效对象，而不仅仅是示例中的9个。
2. 如何同时计算mean value of all these objects？

我认为第二个问题的答案在某种程度上就像这个代码：

mean(c(distM_ref[1:9]_matrix))