dplyr-aggregate聚合数据框

> counts
       cell.1 cell.2 cell.3 cell.4 cell.5
gene.1      2      4      3      3      3
gene.2      6      4      3      3      0
gene.3      1      2      3      3      3
gene.4      8      9      0      3      0

row.agg.list <- c('x_1','x_2','x_1','x_3')
counts %>% data.table::data.table() %>% aggregate(by=list(row.agg.list), FUN=sum) %>% 
    tibble::column_to_rownames(var = "Group.1") 
#######################################
    cell.1 cell.2 cell.3 cell.4 cell.5
x_1      3      6      6      6      6
x_2      6      4      3      3      0
x_3      8      9      0      3      0

col.agg.list <- c('cll.a','cll.a','cell.b','cell.c','cell.c')
counts %>% t() %>% data.table::data.table() %>% aggregate(by=list(col.agg.list), FUN=mean) %>% 
    tibble::column_to_rownames(var = "Group.1") %>% t()
#######################################
       cell.b cell.c cll.a
gene.1      3    3.0   3.0
gene.2      3    1.5   5.0
gene.3      3    3.0   1.5
gene.4      0    1.5   8.5