Question

我在R中有一个名为info的数据框，其中包含Date列下的几个日期，它们以“％Y-％m-％d”排序我希望只有那些相隔不到6天的值且删除“异常值”，任何人都知道如何做到这一点？

数据框的样子

'> info
           Date   ens seps
3    1951-01-08 mem01    2
4    1951-01-12 mem01    4
37   1959-12-08 mem01    4
42   1959-12-30 mem01    3
43   1960-01-01 mem01    2
47   1961-01-03 mem01    2
49   1961-01-18 mem01    2
50   1961-01-20 mem01    2
62   1964-11-29 mem01    4
93   1971-02-12 mem01    2
99   1972-02-15 mem01    2
100  1972-02-18 mem01    3
102  1972-02-21 mem01    2
119  1981-10-16 mem01    3
121  1981-10-19 mem01    2
131  1984-12-24 mem01    2
134  1987-01-02 mem01    2

Answer 1

如果我正确理解了这个问题，那么你可以试试

library(dplyr)

df %>%
  arrange(Date) %>%
  mutate(date_diff = as.numeric(Date - lag(Date))) %>%
  filter(date_diff < 6 | lead(date_diff) < 6) %>%
  select(-date_diff)

输出为：

         Date   ens seps
1  1951-01-08 mem01    2
2  1951-01-12 mem01    4
3  1959-12-30 mem01    3
4  1960-01-01 mem01    2
5  1961-01-18 mem01    2
6  1961-01-20 mem01    2
7  1972-02-15 mem01    2
8  1972-02-18 mem01    3
9  1972-02-21 mem01    2
10 1981-10-16 mem01    3
11 1981-10-19 mem01    2

示例数据：

df <- structure(list(Date = structure(c(-6933, -6929, -3677, -3655, 
-3653, -3285, -3270, -3268, -1859, 407, 775, 778, 781, 4306, 
4309, 5471, 6210), class = "Date"), ens = c("mem01", "mem01", 
"mem01", "mem01", "mem01", "mem01", "mem01", "mem01", "mem01", 
"mem01", "mem01", "mem01", "mem01", "mem01", "mem01", "mem01", 
"mem01"), seps = c(2L, 4L, 4L, 3L, 2L, 2L, 2L, 2L, 4L, 2L, 2L, 
3L, 2L, 3L, 2L, 2L, 2L)), .Names = c("Date", "ens", "seps"), row.names = c("3", 
"4", "37", "42", "43", "47", "49", "50", "62", "93", "99", "100", 
"102", "119", "121", "131", "134"), class = "data.frame")

Answer 2

使用基数R的可能性如下。

inx <- c(TRUE, diff(info$Date) < 6)
new_info <- info[inx, ]
new_info 
#          Date   ens seps
#3   1951-01-08 mem01    2
#4   1951-01-12 mem01    4
#43  1960-01-01 mem01    2
#50  1961-01-20 mem01    2
#100 1972-02-18 mem01    3
#102 1972-02-21 mem01    2
#121 1981-10-19 mem01    2

消除不在上一个日期（R）的特定天数内的日期

2 个答案: