round_date() 不适用于特定的 POSIXct object

Question

我认为这是 lubridate 包中 round_date() 中的错误，但我想确定一下。

这个有效：

round_date(as.POSIXct("2016-10-16 01:00:19", tz = "BRST"))
[1] "2016-10-16 01:00:19 BRST"

这行不通（我只是将参数单位设置为"week"）：

round_date(as.POSIXct("2016-10-16 01:00:19", tz = "BRST"), unit = "week")
[1] NA

这是一个错误还是我遗漏了什么？谢谢。

Session 信息：

> sessionInfo()
R version 3.3.2 (2016-10-31)
Platform: x86_64-w64-mingw32/x64 (64-bit)
Running under: Windows Server >= 2012 x64 (build 9200)

locale:
[1] LC_COLLATE=English_United States.1252  LC_CTYPE=English_United States.1252   
[3] LC_MONETARY=English_United States.1252 LC_NUMERIC=C                          
[5] LC_TIME=English_United States.1252    

attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods   base     

other attached packages:
 [1] dplyr_0.5.0          tidyr_0.6.0          tibble_1.2          
 [4] tidyverse_1.0.0      readr_1.0.0          csutils_0.1.0       
 [7] knitr_1.15.1         DT_0.2               forcats_0.1.1       
[10] purrr_0.2.2          ggrepel_0.6.3        ggplot2_2.1.0       
[13] stringi_1.1.2        lubridate_1.6.0      magrittr_1.5        
[16] randomForest_4.6-12  RevoUtilsMath_10.0.0 RevoUtils_10.0.2    
[19] RevoMods_10.0.0      MicrosoftML_1.0.0    mrsdeploy_1.0       
[22] RevoScaleR_9.0.1     lattice_0.20-34      rpart_4.1-10        
[25] DBI_0.5-1            RODBC_1.3-14        

loaded via a namespace (and not attached):
 [1] Rcpp_0.12.7            plyr_1.8.4             iterators_1.0.8       
 [4] tools_3.3.2            digest_0.6.10          jsonlite_1.1          
 [7] mrupdate_1.0.0         gtable_0.2.0           foreach_1.4.3         
[10] CompatibilityAPI_1.1.0 curl_2.2               stringr_1.1.0         
[13] htmlwidgets_0.7        grid_3.3.2             R6_2.2.0              
[16] scales_0.4.0           codetools_0.2-15       htmltools_0.3.5       
[19] assertthat_0.1         colorspace_1.2-7       lazyeval_0.2.0        
[22] munsell_0.4.3

Answer 1

我认为您需要指定 tz= 参数

x <- as.POSIXct("2016-10-16 01:00:19")
y <- as.POSIXct("2016-10-16 01:00:19", tz = 'BRST')


> lubridate::round_date(x, 'week')
[1] NA
> lubridate::round_date(y, 'week')
[1] "2016-10-16 BRST"
>

区别就在这里：

> attributes(x)
$class
[1] "POSIXct" "POSIXt" 

$tzone
[1] ""

> attributes(y)
$class
[1] "POSIXct" "POSIXt" 

$tzone
[1] "BRST"

如果 unit= 参数不是秒、分、时或日，lubridate::round_date 会尝试在某处获取此属性。

round_date() 不适用于特定的 POSIXct object

round_date() not working for a specific POSIXct object

r

lubridate