資料結構
網路連線
關係資料庫管理系統
作業系統
Java
MS Excel
iOS
HTML
CSS
Android
Python
C 程式設計
C++
C#
MongoDB
MySQL
Javascript
PHP
物理學
化學
生物學
數學
英語
經濟學
心理學
社會學
時尚研究
法律研究如何在 R 中建立具有兩個日期之間日期的向量？
建立包含日期的向量並非易事，但在 seq 和 as.Date 的幫助下，在 R 中卻變得簡單。藉助這些函式，我們可以在 R 中建立一個包含兩個日期之間日期的向量。但不能按相反的順序執行此操作，例如，如果我們希望將未來日期作為向量的第一個元素，那麼這是不可能的。
示例
> V1<-seq(as.Date("2020-01-01"), as.Date("2020-02-28"), by="days")
> V1
[1] "2020-01-01" "2020-01-02" "2020-01-03" "2020-01-04" "2020-01-05"
[6] "2020-01-06" "2020-01-07" "2020-01-08" "2020-01-09" "2020-01-10"
[11] "2020-01-11" "2020-01-12" "2020-01-13" "2020-01-14" "2020-01-15"
[16] "2020-01-16" "2020-01-17" "2020-01-18" "2020-01-19" "2020-01-20"
[21] "2020-01-21" "2020-01-22" "2020-01-23" "2020-01-24" "2020-01-25"
[26] "2020-01-26" "2020-01-27" "2020-01-28" "2020-01-29" "2020-01-30"
[31] "2020-01-31" "2020-02-01" "2020-02-02" "2020-02-03" "2020-02-04"
[36] "2020-02-05" "2020-02-06" "2020-02-07" "2020-02-08" "2020-02-09"
[41] "2020-02-10" "2020-02-11" "2020-02-12" "2020-02-13" "2020-02-14"
[46] "2020-02-15" "2020-02-16" "2020-02-17" "2020-02-18" "2020-02-19"
[51] "2020-02-20" "2020-02-21" "2020-02-22" "2020-02-23" "2020-02-24"
[56] "2020-02-25" "2020-02-26" "2020-02-27" "2020-02-28"
> V1<-seq(as.Date("2020-02-28"), as.Date("2020-01-01"), by="days")
Error in seq.int(0, to0 - from, by) : wrong sign in 'by' argument由於第一個日期位於第二個日期之後，我們因此收到了“’by’ 引數中的符號錯誤”錯誤。
我們來看一些其他的示例 −
> V2<-seq(as.Date("2020-01-01"), as.Date("2020-02-29"), by="days")
> V2
[1] "2020-01-01" "2020-01-02" "2020-01-03" "2020-01-04" "2020-01-05"
[6] "2020-01-06" "2020-01-07" "2020-01-08" "2020-01-09" "2020-01-10"
[11] "2020-01-11" "2020-01-12" "2020-01-13" "2020-01-14" "2020-01-15"
[16] "2020-01-16" "2020-01-17" "2020-01-18" "2020-01-19" "2020-01-20"
[21] "2020-01-21" "2020-01-22" "2020-01-23" "2020-01-24" "2020-01-25"
[26] "2020-01-26" "2020-01-27" "2020-01-28" "2020-01-29" "2020-01-30"
[31] "2020-01-31" "2020-02-01" "2020-02-02" "2020-02-03" "2020-02-04"
[36] "2020-02-05" "2020-02-06" "2020-02-07" "2020-02-08" "2020-02-09"
[41] "2020-02-10" "2020-02-11" "2020-02-12" "2020-02-13" "2020-02-14"
[46] "2020-02-15" "2020-02-16" "2020-02-17" "2020-02-18" "2020-02-19"
[51] "2020-02-20" "2020-02-21" "2020-02-22" "2020-02-23" "2020-02-24"
[56] "2020-02-25" "2020-02-26" "2020-02-27" "2020-02-28" "2020-02-29"
> V2<-seq(as.Date("2020-01-01"), as.Date("2020-02-30"), by="days")
Error in charToDate(x) :
character string is not in a standard unambiguous format
> V2<-seq(as.Date("2020-01-01"), as.Date("2030-02-30"), by="days")
Error in charToDate(x) :
character string is not in a standard unambiguous format錯誤表示該日期 2020-02-30 和 2030-02-30 不存在，因為那是 2 月份。
> V3<-seq(as.Date("2020-06-01"), as.Date("2020-08-01"), by="days")
> V3
[1] "2020-06-01" "2020-06-02" "2020-06-03" "2020-06-04" "2020-06-05"
[6] "2020-06-06" "2020-06-07" "2020-06-08" "2020-06-09" "2020-06-10"
[11] "2020-06-11" "2020-06-12" "2020-06-13" "2020-06-14" "2020-06-15"
[16] "2020-06-16" "2020-06-17" "2020-06-18" "2020-06-19" "2020-06-20"
[21] "2020-06-21" "2020-06-22" "2020-06-23" "2020-06-24" "2020-06-25"
[26] "2020-06-26" "2020-06-27" "2020-06-28" "2020-06-29" "2020-06-30"
[31] "2020-07-01" "2020-07-02" "2020-07-03" "2020-07-04" "2020-07-05"
[36] "2020-07-06" "2020-07-07" "2020-07-08" "2020-07-09" "2020-07-10"
[41] "2020-07-11" "2020-07-12" "2020-07-13" "2020-07-14" "2020-07-15"
[46] "2020-07-16" "2020-07-17" "2020-07-18" "2020-07-19" "2020-07-20"
[51] "2020-07-21" "2020-07-22" "2020-07-23" "2020-07-24" "2020-07-25"
[56] "2020-07-26" "2020-07-27" "2020-07-28" "2020-07-29" "2020-07-30"
[61] "2020-07-31" "2020-08-01"
更新於: 12-Aug-2020
2K+ 瀏覽量
廣告