按两列排序数据框(带条件)

Question

我在R中有以下数据框:

DataTable <- data.frame( Name = c("Nelle","Alex","Thomas","Jeff","Rodger","Michi"), Age = c(17, 18, 18, 16, 16, 16), Grade = c(1,5,3,2,2,4) )

    Name Age Grade
1  Nelle  17     1
2   Alex  18     5
3 Thomas  18     3
4   Jeff  16     2
5 Rodger  16     2
6  Michi  16     4

现在生病将按其Age列对该数据框进行排序.到目前为止没问题:

DataTable_sort_age <- DataTable[with(DataTable, order(DataTable[,2])),]

    Name Age Grade
4   Jeff  16     2
5 Rodger  16     2
6  Michi  16     4
1  Nelle  17     1
2   Alex  18     5
3 Thomas  18     3

Name列中有更多人具有相同的年龄,应按字母顺序排序.如果多个人处于同一年龄的条件为真,则数据框应按字母顺序排序Name.输出应如下所示:

    Name Age Grade
1   Jeff  16     2
2  Michi  16     2
3 Rodger  16     4
4  Nelle  17     1
5   Alex  18     5
6 Thomas  18     3

希望您能按字母顺序排序数据框来帮助我.

Answer 1

根据@Stezzo的评论更新答案

只需DataTable[, 1]在order功能中 添加即可

DataTable[order(DataTable[,2], DataTable[, 1]),]

#    Name Age Grade
# 4   Jeff  16     2
# 6  Michi  16     4
# 5 Rodger  16     2
# 1  Nelle  17     1
# 2   Alex  18     5
# 3 Thomas  18     3

请记住,参数传递的顺序很重要.它首先会对第二列的DataTable数据帧进行排序,如果是平局,它会考虑第二个参数,即第一列.