levels(x = pbmc) # 存放细胞identity classes pbmc[["old.ident"]] <- Idents(object = pbmc) #将"old.ident"存放在pbmc的metadata中 # 设置identity classes Idents(object = pbmc) <- "CD4 T cells" #将"CD4 T cells"设置为pbmc的 "active.ident" Idents(object = pbmc, cells = 1:10) <- "...