If m is stored in R (as it is by default), then m2 <- copy.msa(m1) is no different than m2 <- m1. But if it is stored as a pointer to a C structure, this is the only way to make an explicit copy
如果M是存储在R(,因为它是默认设置),然后M2 < - copy.msa(M1)是没有什么不同比m2 - M1。但是,如果它被存储为一个指针,指向一个C结构,这是唯一的方式做出明确的副本
值----------Value----------
an MSA object which can be modified independently from the
一个MSA对象,可以独立于修改