每组唯一值的累积计数

user2363642 发表于 Dev

用户名

我有一个df，上面有姓名和某些资格日期。我想创建一个根据时间显示一个人有多少个elig_end_date的指标。这是我的df：

 names date_of_claim elig_end_date
1    tom    2010-01-01    2010-07-01
2    tom    2010-05-04    2010-07-01
3    tom    2010-06-01    2014-01-01
4    tom    2010-10-10    2014-01-01
5   mary    2010-03-01    2014-06-14
6   mary    2010-05-01    2014-06-14
7   mary    2010-08-01    2014-06-14
8   mary    2010-11-01    2014-06-14
9   mary    2011-01-01    2014-06-14
10  john    2010-03-27    2011-03-01
11  john    2010-07-01    2011-03-01
12  john    2010-11-01    2011-03-01
13  john    2011-02-01    2011-03-01

这是我想要的输出：

 names date_of_claim elig_end_date obs
1    tom    2010-01-01    2010-07-01   1
2    tom    2010-05-04    2010-07-01   1
3    tom    2010-06-01    2014-01-01   2
4    tom    2010-10-10    2014-01-01   2
5   mary    2010-03-01    2014-06-14   1
6   mary    2010-05-01    2014-06-14   1
7   mary    2010-08-01    2014-06-14   1
8   mary    2010-11-01    2014-06-14   1
9   mary    2011-01-01    2014-06-14   1
10  john    2010-03-27    2011-03-01   1
11  john    2010-07-01    2011-03-01   1
12  john    2010-11-01    2011-03-01   1
13  john    2011-02-01    2011-03-01   1

我发现这篇文章很有用R：按类别计数唯一值，但答案是作为单独的表给出的，而不是包含在df中。

我也尝试过这个：

df$ob = ave(df$elig_end_date, df$elig_end_date, FUN=seq_along)

但这会产生一个计数，我真的只想要一个指标。

先感谢您

STEPHEN's CODE的产品（这不是正确的代码-只是发布作为学习要点）

names date_of_claim elig_end_date ob
1    tom    2010-01-01    2010-07-01  2
2    tom    2010-05-04    2010-07-01  2
3    tom    2010-06-01    2014-01-01  2
4    tom    2010-10-10    2014-01-01  2
5   mary    2010-03-01    2014-06-14  5
6   mary    2010-05-01    2014-06-14  5
7   mary    2010-08-01    2014-06-14  5
8   mary    2010-11-01    2014-06-14  5
9   mary    2011-01-01    2014-06-14  5
10  john    2010-03-27    2011-03-01  4
11  john    2010-07-01    2011-03-01  4
12  john    2010-11-01    2011-03-01  4
13  john    2011-02-01    2011-03-01  4

亨里克

使用的另一种可能性ave：

df$obs <- with(df, ave(elig_end_date, names,
                       FUN = function(x) cumsum(!duplicated(x))))

#    names date_of_claim elig_end_date obs
# 1    tom    2010-01-01    2010-07-01   1
# 2    tom    2010-05-04    2010-07-01   1
# 3    tom    2010-06-01    2014-01-01   2
# 4    tom    2010-10-10    2014-01-01   2
# 5   mary    2010-03-01    2014-06-14   1
# 6   mary    2010-05-01    2014-06-14   1
# 7   mary    2010-08-01    2014-06-14   1
# 8   mary    2010-11-01    2014-06-14   1
# 9   mary    2011-01-01    2014-06-14   1
# 10  john    2010-03-27    2011-03-01   1
# 11  john    2010-07-01    2011-03-01   1
# 12  john    2010-11-01    2011-03-01   1
# 13  john    2011-02-01    2011-03-01   1