1. 修改的需求
#例如你用以下table
dt = data.table(id = c('id1','id2','id3','id4','id5','id6'), sample = c("MER-1,MER-3,MER-4","MER-5","MER-2","MER-2,MER-3,MER-4,MER-5","MER_3","MER-5" ))
dt
id sample
1: id1 MER-1,MER-3,MER-4
2: id2 MER-5
3: id3 MER-2
4: id4 MER-2,MER-3,MER-4,MER-5
5: id5 MER_3
6: id6 MER-5
#你要转化为以下矩阵
MER-1 MER-2 MER-3 MER-4 MER-5
id1 1 0 0 1 0
id2 0 0 0 1 0
id3 1 0 0 0 0
id4 1 1 0 0 0
id5 0 0 1 1 0
id6 0 1 1 0 1
2.在R中实现目的
table(dt[,unlist(strsplit(sample,",")),by=id])
V1
id MER-1 MER-2 MER-3 MER-4 MER-5 MER_3
id1 1 0 1 1 0 0
id2 0 0 0 0 1 0
id3 0 1 0 0 0 0
id4 0 1 1 1 1 0
id5 0 0 0 0 0 1
id6 0 0 0 0 1 0
