小编grr*_*man的帖子

我有一个数据集存储为data.table DT,如下所示:

print(DT)
   category            industry
1: administration      admin
2: nurse practitioner  truck
3: trucking            truck
4: administration      admin
5: warehousing         nurse
6: warehousing         admin
7: trucking            truck
8: nurse practitioner  nurse         
9: nurse practitioner  truck 

我想将表格减少到只有行业与该类别匹配的行.我的一般方法是使用grepl()正则表达式匹配字符串'^{{INDUSTRY}}[a-z ]+$'和每一行DT$category,每个对应的行DT$industry插入在{{INDUSTRY}}正则表达式字符串中使用infuse().我很难找到一个时髦的data.table解决方案,它可以正确地循环遍历表并进行行内比较,所以我使用for循环来完成工作:

template <- "^{{IND}}[a-z ]+$"
DT[,match := FALSE,]
for (i in seq(1,length(DT$category))) {
    ind <- DT[i]$industry
    categ <- d.daily[i]$category
    if (grepl(infuse(IND=ind,template),categ)){
        DT[i]$match <- TRUE
    }
}
DT<- DT[match==TRUE]
print(DT)
       category            industry …