比较 R 中不同行中的不同列答案

【问题标题】：Compare different columns in separate rows in R比较 R 中不同行中的不同列
【发布时间】：2014-01-06 19:52:15
【问题描述】：

我想检查个人的资格状态是否存在任何差距。我将间隔定义为在最后一个 elig_end_date 之后 30 天发生的 date_of_claim。因此，我想做的是检查每个 date_of_claim 是否不超过 elig_end_date +30days 紧接在前面的行中。理想情况下，我想要一个指标，0 表示没有差距，1 表示每人有差距以及差距发生在哪里。这是一个示例 df，其解决方案内置为“间隙”。

 names date_of_claim elig_end_date obs gaps
1    tom    2010-01-01    2010-07-01   1    NA
2    tom    2010-05-04    2010-07-01   1    0
3    tom    2010-06-01    2014-01-01   2    0
4    tom    2010-10-10    2014-01-01   2    0
5   mary    2010-03-01    2014-06-14   1    NA
6   mary    2010-05-01    2014-06-14   1    0
7   mary    2010-08-01    2014-06-14   1    0
8   mary    2010-11-01    2014-06-14   1    0
9   mary    2011-01-01    2014-06-14   1    0
10  john    2010-03-27    2011-03-01   1    NA
11  john    2010-07-01    2011-03-01   1    0
12  john    2010-11-01    2011-03-01   1    0
13  john    2011-02-01    2011-03-01   1    0
14   sue    2010-02-01    2010-04-30   1    NA
15   sue    2010-02-27    2010-04-30   1    0
16   sue    2010-03-13    2010-05-31   2    0
17   sue    2010-04-27    2010-06-30   3    0
18   sue    2010-04-27    2010-06-30   3    0
19   sue    2010-05-06    2010-08-31   4    0
20   sue    2010-06-08    2010-09-30   5    0
21  mike    2010-05-01    2010-07-30   1    NA
22  mike    2010-06-01    2010-07-30   1    0
23  mike    2010-11-12    2011-07-30   2    1

我发现这篇文章非常有用How can I compare a value in a column to the previous one using R?，但我觉得我不能使用循环，因为我的 df 有 400 万行，而且我已经很难在上面运行循环了。

为此，我认为我需要的代码是这样的：

df$gaps<-ifelse(df$date_of_claim>=df$elig_end_date+30,1,0)  ##this doesn't use the preceeding row.

我用这个做了一个笨拙的尝试：

df$gaps<-df$date_of_claim>=df$elig_end_date[-1,]

但我收到一条错误消息，提示我的维度数不正确。

非常感谢所有帮助！谢谢。

【问题讨论】：

标签： r rows col

【解决方案1】：

如果有四百万个观察值，我会使用 data.table：

DF <- read.table(text="names date_of_claim elig_end_date obs gaps
1    tom    2010-01-01    2010-07-01   1    NA
2    tom    2010-05-04    2010-07-01   1    0
3    tom    2010-06-01    2014-01-01   2    0
4    tom    2010-10-10    2014-01-01   2    0
5   mary    2010-03-01    2014-06-14   1    NA
6   mary    2010-05-01    2014-06-14   1    0
7   mary    2010-08-01    2014-06-14   1    0
8   mary    2010-11-01    2014-06-14   1    0
9   mary    2011-01-01    2014-06-14   1    0
10  john    2010-03-27    2011-03-01   1    NA
11  john    2010-07-01    2011-03-01   1    0
12  john    2010-11-01    2011-03-01   1    0
13  john    2011-02-01    2011-03-01   1    0
14   sue    2010-02-01    2010-04-30   1    NA
15   sue    2010-02-27    2010-04-30   1    0
16   sue    2010-03-13    2010-05-31   2    0
17   sue    2010-04-27    2010-06-30   3    0
18   sue    2010-04-27    2010-06-30   3    0
19   sue    2010-05-06    2010-08-31   4    0
20   sue    2010-06-08    2010-09-30   5    0
21  mike    2010-05-01    2010-07-30   1    NA
22  mike    2010-06-01    2010-07-30   1    0
23  mike    2010-11-12    2011-07-30   2    1", header=TRUE)

library(data.table)
DT <- data.table(DF)

DT[, c("date_of_claim", "elig_end_date") := list(as.Date(date_of_claim), as.Date(elig_end_date))]

DT[, gaps2:= c(NA, date_of_claim[-1] > head(elig_end_date, -1)+30), by=names]

#    names date_of_claim elig_end_date obs gaps gaps2
# 1:   tom    2010-01-01    2010-07-01   1   NA    NA
# 2:   tom    2010-05-04    2010-07-01   1    0 FALSE
# 3:   tom    2010-06-01    2014-01-01   2    0 FALSE
# 4:   tom    2010-10-10    2014-01-01   2    0 FALSE
# 5:  mary    2010-03-01    2014-06-14   1   NA    NA
# 6:  mary    2010-05-01    2014-06-14   1    0 FALSE
# 7:  mary    2010-08-01    2014-06-14   1    0 FALSE
# 8:  mary    2010-11-01    2014-06-14   1    0 FALSE
# 9:  mary    2011-01-01    2014-06-14   1    0 FALSE
# 10:  john    2010-03-27    2011-03-01   1   NA    NA
# 11:  john    2010-07-01    2011-03-01   1    0 FALSE
# 12:  john    2010-11-01    2011-03-01   1    0 FALSE
# 13:  john    2011-02-01    2011-03-01   1    0 FALSE
# 14:   sue    2010-02-01    2010-04-30   1   NA    NA
# 15:   sue    2010-02-27    2010-04-30   1    0 FALSE
# 16:   sue    2010-03-13    2010-05-31   2    0 FALSE
# 17:   sue    2010-04-27    2010-06-30   3    0 FALSE
# 18:   sue    2010-04-27    2010-06-30   3    0 FALSE
# 19:   sue    2010-05-06    2010-08-31   4    0 FALSE
# 20:   sue    2010-06-08    2010-09-30   5    0 FALSE
# 21:  mike    2010-05-01    2010-07-30   1   NA    NA
# 22:  mike    2010-06-01    2010-07-30   1    0 FALSE
# 23:  mike    2010-11-12    2011-07-30   2    1  TRUE
#     names date_of_claim elig_end_date obs gaps gaps2

【讨论】：