我发现运行 R 2.12.1 的两个环境之间的行为差异。在第一个中,动物园的行为符合预期。
> library(zoo)
> x.date <- as.Date(paste(2003, 2, c(1, 3, 7, 9, 14), sep = "-"))
> x <- zoo(rnorm(5), x.date)
> index(x)
[1] "2003-02-01" "2003-02-03" "2003-02-07" "2003-02-09" "2003-02-14"
> as.Date(index(x))
[1] "2003-02-01" "2003-02-03" "2003-02-07" "2003-02-09" "2003-02-14"
> sessionInfo()
R version 2.12.1 (2010-12-16)
Platform: x86_64-unknown-linux-gnu (64-bit)
locale:
[1] C
attached base packages:
[1] grid stats graphics grDevices utils datasets methods base
other attached packages:
[1] ggplot2_0.8.9 proto_0.3-9.1 reshape_0.8.4 MASS_7.3-9 plyr_1.4 RODBC_1.3-2 zoo_1.6-4
loaded via a namespace (and not attached):
[1] lattice_0.19-13 tools_2.12.1
在另一个我得到以下输出:
> library(zoo)
> x.date <- as.Date(paste(2003, 2, c(1, 3, 7, 9, 14), sep = "-"))
> x <- zoo(rnorm(5), x.date)
> index(x)
[1] "02/01/2003 00:00:00.000 UTC" "02/03/2003 00:00:00.000 UTC" "02/07/2003 00:00:00.000 UTC" "02/09/2003 00:00:00.000 UTC" "02/14/2003 00:00:00.000 UTC"
> as.Date(index(x))
[1] "02/01/2003 00:00:00.000 UTC" "02/03/2003 00:00:00.000 UTC" "02/07/2003 00:00:00.000 UTC" "02/09/2003 00:00:00.000 UTC" "02/14/2003 00:00:00.000 UTC"
> sessionInfo()
R version 2.12.1 (2010-12-16)
Platform: x86_64-unknown-linux-gnu (64-bit)
locale:
[1] C
attached base packages:
[1] grid grDevices graphics stats datasets utils methods base
other attached packages:
[1] zoo_1.6-4 ggplot2_0.8.9 proto_0.3-8 reshape_0.8.4 plyr_1.4
loaded via a namespace (and not attached):
[1] digest_0.4.2 lattice_0.19-13
不仅奇怪,而且后一种行为会导致来自 ggplot2 的错误消息。有什么见解吗?提前致谢。