日期序列中的 While 循环

While loop in Date sequence

提问人：Zohaib 提问时间：3/14/2023 最后编辑：Darren TsaiZohaib 更新时间：3/16/2023 访问量：133

问：

下面提到的代码是否有任何循环？

library(lubridate)

Val_Date <- as.Date("2022-01-1", format = "%Y-%m-%d")
Inception_Date <- as.Date("2012-01-01", format = "%Y-%m-%d")

a  <- data.frame(Date = seq(Inception_Date, Val_Date, by = "years"))
b  <- data.frame(Date = seq(Inception_Date + years(1), Val_Date, by = "years"))
c  <- data.frame(Date = seq(Inception_Date + years(2), Val_Date, by = "years"))
d  <- data.frame(Date = seq(Inception_Date + years(3), Val_Date, by = "years"))
e  <- data.frame(Date = seq(Inception_Date + years(4), Val_Date, by = "years"))
f  <- data.frame(Date = seq(Inception_Date + years(5), Val_Date, by = "years"))
g  <- data.frame(Date = seq(Inception_Date + years(6), Val_Date, by = "years"))
h  <- data.frame(Date = seq(Inception_Date + years(7), Val_Date, by = "years"))
i  <- data.frame(Date = seq(Inception_Date + years(8), Val_Date, by = "years"))
j  <- data.frame(Date = seq(Inception_Date + years(9), Val_Date, by = "years"))
k  <- data.frame(Date = seq(Inception_Date + years(10), Val_Date, by = "years"))

complete <- rbind(a, b, c, d, e, f, g, h, i, j, k)

在我的中等于 ，所以我需要循环，因为每次我的值日期增加时，我都想添加一行新的代码。kInception_Date + year(10)val_Date

r 日期 while-loop 序列

评论

0赞 Where's my towel 3/14/2023
我不太清楚你到底想达到什么目的。但是当遍历一组元素（这里是：日期）时，for（） 循环似乎是更直接的解决方案：for(currentdate in a){print(currentdate)}
0赞 Community 3/14/2023
请澄清您的具体问题或提供其他详细信息，以准确说明您的需求。正如目前所写的那样，很难确切地说出你在问什么。

答：

0赞 dandrews 3/14/2023 #1 
for (i in unique(a)) {
  print(i)
# Edit to adrees OP's comment
  x=as.Date(a[i,1])
  seq(x,length=2,by='1 year')[2]
}

至于存储结果，您可以使用列表，然后将其制作成数据帧。do.call

mylist <- list()
for (i in 1:length(a$Date)) {
  mylist[[i]]=a[i,1]
}

do.call('rbind',mylist)

另一种选择

for (i in seq.Date(from = Inception_Date,to=Val_Date,by='year')) {
  print(i)
# do other stuff
}

评论

0赞 dandrews 3/14/2023
没关系，只需在这两个循环中的任何一个中添加一个调用来提前日期，它就会在每次迭代中自动这样做。我只是使用了这些简单的例子，因为你没有提供足够的信息让我确切地知道你想要实现什么。
0赞 dandrews 3/14/2023
我为一个选项在第一个循环中添加了两行，请参阅此处 stackoverflow.com/questions/3312964/how-to-subtract-years
0赞 dandrews 3/15/2023
请注意，OP 删除了他们的评论并更新了问题，因此这些答案现在可能超出了新问题的范围。
1赞 Darren Tsai 3/14/2023 #2
  • 递归解决方案：
date_seq_recur <- function(start, end) {
  if(start <= end)
    c(seq(start, end, by = "year"), date_seq_recur(start + years(1), end))
}

date_seq_recur(Inception_Date, Val_Date)
  • while-圈：
date_seq_while <- function(start, end) {
  date <- as.Date(numeric())
  while(start <= end) {
    date <- c(date, seq(start, end, by = "year"))
    start <- start + years(1)
  }
  return(date)
}

date_seq_while(Inception_Date, Val_Date)
外出
#  [1] "2012-01-01" "2013-01-01" "2014-01-01" "2015-01-01" "2016-01-01" "2017-01-01"
#  [7] "2018-01-01" "2019-01-01" "2020-01-01" "2021-01-01" "2022-01-01" "2013-01-01"
# [13] "2014-01-01" "2015-01-01" "2016-01-01" "2017-01-01" "2018-01-01" "2019-01-01"
# [19] "2020-01-01" "2021-01-01" "2022-01-01" "2014-01-01" "2015-01-01" "2016-01-01"
# [25] "2017-01-01" "2018-01-01" "2019-01-01" "2020-01-01" "2021-01-01" "2022-01-01"
# [31] "2015-01-01" "2016-01-01" "2017-01-01" "2018-01-01" "2019-01-01" "2020-01-01"
# [37] "2021-01-01" "2022-01-01" "2016-01-01" "2017-01-01" "2018-01-01" "2019-01-01"
# [43] "2020-01-01" "2021-01-01" "2022-01-01" "2017-01-01" "2018-01-01" "2019-01-01"
# [49] "2020-01-01" "2021-01-01" "2022-01-01" "2018-01-01" "2019-01-01" "2020-01-01"
# [55] "2021-01-01" "2022-01-01" "2019-01-01" "2020-01-01" "2021-01-01" "2022-01-01"
# [61] "2020-01-01" "2021-01-01" "2022-01-01" "2021-01-01" "2022-01-01" "2022-01-01"

评论

0赞 Zohaib 3/14/2023
如果我想再添加一列，重复 （length（seq（Inception_Date， Val_Date， by = “years”）） 乘以 Inception_Date 年。
0赞 Zohaib 3/14/2023
例如，这样的代码 Int_Yr_0 = length（seq（as.日期（Inception_Date），作为。Date（Val_Date）， by =“years”）） a<- data.frame（Int_Yr = seq（as.日期（Inception_Date），作为。Date（Val_Date）， by =“years”）， Loss_Yr = rep（as.numeric（format（Inception_Date，'%Y'），Int_Yr_0））） 像这样有第二列loss_year
0赞 Darren Tsai 3/14/2023
@Zohaibdates <- seq(Inception_Date, Val_Date, by = "years"); rep(format(dates, '%Y'), rev(seq_along(dates)))
2赞 Merijn van Tilborg 3/14/2023 #3

我建议创建一次日期序列，然后使用 with 创建索引号序列，然后根据该序列子集日期。sequencefrom = 

dates <- seq(as.Date("2012-01-1"),as.Date("2022-01-1"), by ="years")

n <- length(dates)

dates[sequence(n:1, from = 1:n)]

# [1] "2012-01-01" "2013-01-01" "2014-01-01" "2015-01-01" "2016-01-01" "2017-01-01" "2018-01-01" "2019-01-01" "2020-01-01" "2021-01-01" "2022-01-01" "2013-01-01"
# [13] "2014-01-01" "2015-01-01" "2016-01-01" "2017-01-01" "2018-01-01" "2019-01-01" "2020-01-01" "2021-01-01" "2022-01-01" "2014-01-01" "2015-01-01" "2016-01-01"
# [25] "2017-01-01" "2018-01-01" "2019-01-01" "2020-01-01" "2021-01-01" "2022-01-01" "2015-01-01" "2016-01-01" "2017-01-01" "2018-01-01" "2019-01-01" "2020-01-01"
# [37] "2021-01-01" "2022-01-01" "2016-01-01" "2017-01-01" "2018-01-01" "2019-01-01" "2020-01-01" "2021-01-01" "2022-01-01" "2017-01-01" "2018-01-01" "2019-01-01"
# [49] "2020-01-01" "2021-01-01" "2022-01-01" "2018-01-01" "2019-01-01" "2020-01-01" "2021-01-01" "2022-01-01" "2019-01-01" "2020-01-01" "2021-01-01" "2022-01-01"
# [61] "2020-01-01" "2021-01-01" "2022-01-01" "2021-01-01" "2022-01-01" "2022-01-01"
0赞 Nick Chr 3/16/2023 #4

使用 from timeplyr，这是一个矢量化时间序列函数，可以处理润滑周期/持续时间以及非整数增量。time_seq_v()

# remotes::install_github("NicChr/timeplyr")
library(timeplyr)
library(lubridate)
Val_Date <- as.Date("2022-01-1", format = "%Y-%m-%d")
Inception_Date <- as.Date("2012-01-01", format = "%Y-%m-%d")

time_seq_v(Inception_Date + years(0:10), Val_Date, units = "years", num = 1)
#>  [1] "2012-01-01" "2013-01-01" "2014-01-01" "2015-01-01" "2016-01-01"
#>  [6] "2017-01-01" "2018-01-01" "2019-01-01" "2020-01-01" "2021-01-01"
#> [11] "2022-01-01" "2013-01-01" "2014-01-01" "2015-01-01" "2016-01-01"
#> [16] "2017-01-01" "2018-01-01" "2019-01-01" "2020-01-01" "2021-01-01"
#> [21] "2022-01-01" "2014-01-01" "2015-01-01" "2016-01-01" "2017-01-01"
#> [26] "2018-01-01" "2019-01-01" "2020-01-01" "2021-01-01" "2022-01-01"
#> [31] "2015-01-01" "2016-01-01" "2017-01-01" "2018-01-01" "2019-01-01"
#> [36] "2020-01-01" "2021-01-01" "2022-01-01" "2016-01-01" "2017-01-01"
#> [41] "2018-01-01" "2019-01-01" "2020-01-01" "2021-01-01" "2022-01-01"
#> [46] "2017-01-01" "2018-01-01" "2019-01-01" "2020-01-01" "2021-01-01"
#> [51] "2022-01-01" "2018-01-01" "2019-01-01" "2020-01-01" "2021-01-01"
#> [56] "2022-01-01" "2019-01-01" "2020-01-01" "2021-01-01" "2022-01-01"
#> [61] "2020-01-01" "2021-01-01" "2022-01-01" "2021-01-01" "2022-01-01"
#> [66] "2022-01-01"

创建于 2023-03-16 使用 reprex v2.0.2

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