如何在R中对年份季度列（time）按时间先后排序

针对你提供的time列格式为T1/YYYY（T1-T4代表季度）的data.table数据集，以下两种方法可以实现从过去到现在的时间排序：

方法一：拆分年份和季度字段排序 #

这种方法无需额外依赖包，直接通过拆分time列提取年份和季度信息，再按这两个字段排序：

library(data.table)

# 加载你的数据集
dt <- structure(list(time = c("T2/2023", "T1/2023", "T4/2022", "T3/2022", 
"T2/2022", "T1/2022"), PIB = c(73050L, 71798L, 68247L, 68652L, 
67968L, 65843L), `Valor afegit brut` = c(67426L, 66399L, 64218L, 
63228L, 62436L, 60339L), Agricultura = c(756L, 689L, 384L, 404L, 
405L, 429L), Indústria = c(13281L, 13172L, 12710L, 12715L, 12557L, 
12204L), Construcció = c(3112L, 3030L, 2872L, 2832L, 2788L, 
2736L), Serveis = c(50277L, 49508L, 48252L, 47276L, 46686L, 44970L
), `Comerç, transport i hostaleria` = c(17737L, 17301L, 16455L, 
16009L, 15959L, 15007L), `Act. immobiliàries, professionals i altres` = c(22085L, 
21974L, 21768L, 21269L, 20820L, 20210L), `Adm. pública, educació, sanitat i serveis socials` = c(10455L, 
10233L, 10030L, 9998L, 9908L, 9753L), `Impostos nets sobre productes` = c(5624L, 
5399L, 4028L, 5424L, 5532L, 5504L)), row.names = c(NA, -6L), class = c("data.table", 
"data.frame"))

# 拆分time列，提取季度和年份
dt[, c("quarter", "year") := tstrsplit(time, "/")]
dt[, quarter := as.integer(sub("T", "", quarter))]
dt[, year := as.integer(year)]

# 按年份、季度升序排序（从过去到现在）
dt_sorted <- dt[order(year, quarter)]

# 可选：删除临时生成的quarter和year列
dt_sorted[, c("quarter", "year") := NULL]

方法二：使用zoo包转换为季度时间对象排序 #

借助zoo包的as.yearqtr函数，可以直接将time列转换为可排序的季度时间类型：

library(data.table)
library(zoo)

# 加载数据集（同方法一）
dt <- structure(list(time = c("T2/2023", "T1/2023", "T4/2022", "T3/2022", 
"T2/2022", "T1/2022"), PIB = c(73050L, 71798L, 68247L, 68652L, 
67968L, 65843L), `Valor afegit brut` = c(67426L, 66399L, 64218L, 
63228L, 62436L, 60339L), Agricultura = c(756L, 689L, 384L, 404L, 
405L, 429L), Indústria = c(13281L, 13172L, 12710L, 12715L, 12557L, 
12204L), Construcció = c(3112L, 3030L, 2872L, 2832L, 2788L, 
2736L), Serveis = c(50277L, 49508L, 48252L, 47276L, 46686L, 44970L
), `Comerç, transport i hostaleria` = c(17737L, 17301L, 16455L, 
16009L, 15959L, 15007L), `Act. immobiliàries, professionals i altres` = c(22085L, 
21974L, 21768L, 21269L, 20820L, 20210L), `Adm. pública, educació, sanitat i serveis socials` = c(10455L, 
10233L, 10030L, 9998L, 9908L, 9753L), `Impostos nets sobre productes` = c(5624L, 
5399L, 4028L, 5424L, 5532L, 5504L)), row.names = c(NA, -6L), class = c("data.table", 
"data.frame"))

# 将time列转换为yearqtr格式
dt[, time_qtr := as.yearqtr(time, format = "T%q/%Y")]

# 按转换后的季度时间升序排序
dt_sorted <- dt[order(time_qtr)]

# 可选：删除临时生成的time_qtr列
dt_sorted[, time_qtr := NULL]

两种方法最终都会得到按T1/2022 → T2/2022 → T3/2022 → T4/2022 → T1/2023 → T2/2023顺序排列的数据集。

内容的提问来源于stack exchange，提问作者Maria