要从日期查找一年中的某天，我们可以使用lubridate包的yday函数。例如，如果我们有一个向量的日期或日期，则只需使用以下语法在yday函数中传递该日期或向量-
yday(“date”)
要么
yday(“vector_of_date”)
加载润滑包装-
library(lubridate)
date1<-"2020-01-01"
yday(date1)
[1] 1
date2<-"2020-01-25"
yday(date2)
[1] 25
date3<-c("2020-01-25","2020-01-15","2020-02-25","2020-10-03","2020-02-25","2020-05-15","2020-01-28","2020-01-20","2020-11-25","2020-12-25","2020-01-05","2020-06-21","2020-06-22","2020-02-20","2020-03-18","2020-04-19","2020-04-04","2020-04-29","2020-01-03","2020-01-17","2020-11-05","2020-09-09","2020-10-09","2020-04-14","2020-10-02","2020-12-03","2020-11-07","2020-08-15","2020-07-22","2020-07-25","2020-08-25","2020-05-07","2020-05-23","2020-04-01","2020-04-30","2020-07-15","2020-08-17","2020-09-12","2020-10-03","2020-11-16","2020-01-11","2020-06-06","2020-07-24")
date3
[1] "2020-01-25" "2020-01-15" "2020-02-25" "2020-10-03" "2020-02-25"
[6] "2020-05-15" "2020-01-28" "2020-01-20" "2020-11-25" "2020-12-25"
[11] "2020-01-05" "2020-06-21" "2020-06-22" "2020-02-20" "2020-03-18"
[16] "2020-04-19" "2020-04-04" "2020-04-29" "2020-01-03" "2020-01-17"
[21] "2020-11-05" "2020-09-09" "2020-10-09" "2020-04-14" "2020-10-02"
[26] "2020-12-03" "2020-11-07" "2020-08-15" "2020-07-22" "2020-07-25"
[31] "2020-08-25" "2020-05-07" "2020-05-23" "2020-04-01" "2020-04-30"
[36] "2020-07-15" "2020-08-17" "2020-09-12" "2020-10-03" "2020-11-16"
[41] "2020-01-11" "2020-06-06" "2020-07-24"
yday(date3)
[1] 25 15 56 277 56 136 28 20 330 360 5 173 174 51 78 110 95 120 3
[20] 17 310 253 283 105 276 338 312 228 204 207 238 128 144 92 121 197 230 256
[39] 277 321 11 158 206
date4<-seq(as.Date("2020-01-01"),as.Date("2020-04-01"),by="days")
date4
[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"
[61] "2020-03-01" "2020-03-02" "2020-03-03" "2020-03-04" "2020-03-05"
[66] "2020-03-06" "2020-03-07" "2020-03-08" "2020-03-09" "2020-03-10"
[71] "2020-03-11" "2020-03-12" "2020-03-13" "2020-03-14" "2020-03-15"
[76] "2020-03-16" "2020-03-17" "2020-03-18" "2020-03-19" "2020-03-20"
[81] "2020-03-21" "2020-03-22" "2020-03-23" "2020-03-24" "2020-03-25"
[86] "2020-03-26" "2020-03-27" "2020-03-28" "2020-03-29" "2020-03-30"
[91] "2020-03-31" "2020-04-01"
yday(date4)
[1] 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25
[26] 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
[51] 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75
[76] 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92
date5<-seq(as.Date("2020-01-01"),as.Date("2020-06-01"),by="2 days")
date5
[1] "2020-01-01" "2020-01-03" "2020-01-05" "2020-01-07" "2020-01-09"
[6] "2020-01-11" "2020-01-13" "2020-01-15" "2020-01-17" "2020-01-19"
[11] "2020-01-21" "2020-01-23" "2020-01-25" "2020-01-27" "2020-01-29"
[16] "2020-01-31" "2020-02-02" "2020-02-04" "2020-02-06" "2020-02-08"
[21] "2020-02-10" "2020-02-12" "2020-02-14" "2020-02-16" "2020-02-18"
[26] "2020-02-20" "2020-02-22" "2020-02-24" "2020-02-26" "2020-02-28"
[31] "2020-03-01" "2020-03-03" "2020-03-05" "2020-03-07" "2020-03-09"
[36] "2020-03-11" "2020-03-13" "2020-03-15" "2020-03-17" "2020-03-19"
[41] "2020-03-21" "2020-03-23" "2020-03-25" "2020-03-27" "2020-03-29"
[46] "2020-03-31" "2020-04-02" "2020-04-04" "2020-04-06" "2020-04-08"
[51] "2020-04-10" "2020-04-12" "2020-04-14" "2020-04-16" "2020-04-18"
[56] "2020-04-20" "2020-04-22" "2020-04-24" "2020-04-26" "2020-04-28"
[61] "2020-04-30" "2020-05-02" "2020-05-04" "2020-05-06" "2020-05-08"
[66] "2020-05-10" "2020-05-12" "2020-05-14" "2020-05-16" "2020-05-18"
[71] "2020-05-20" "2020-05-22" "2020-05-24" "2020-05-26" "2020-05-28"
[76] "2020-05-30" "2020-06-01"
yday(date5)
[1] 1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37
[20] 39 41 43 45 47 49 51 53 55 57 59 61 63 65 67 69 71 73 75
[39] 77 79 81 83 85 87 89 91 93 95 97 99 101 103 105 107 109 111 113
[58] 115 117 119 121 123 125 127 129 131 133 135 137 139 141 143 145 147 149 151
[77] 153