The R Project SVN
R
(root)/branches/R-syntax/tests/datetime2.Rout.save – Rev 83796
Rev 81507 | Blame | Compare with Previous | Last modification | View Log | Download | RSS feed
R Under development (unstable) (2022-11-07 r83301) -- "Unsuffered Consequences"Copyright (C) 2022 The R Foundation for Statistical ComputingPlatform: aarch64-apple-darwin22.1.0 (64-bit)R is free software and comes with ABSOLUTELY NO WARRANTY.You are welcome to redistribute it under certain conditions.Type 'license()' or 'licence()' for distribution details.R is a collaborative project with many contributors.Type 'contributors()' for more information and'citation()' on how to cite R or R packages in publications.Type 'demo()' for some demos, 'help()' for on-line help, or'help.start()' for an HTML browser interface to help.Type 'q()' to quit R.> ### Tests of often platform-dependent features of the POSIX[cl]t implementation.>> ### Expect differences, especially with 32-bit time_t and platforms> ### without tm_zone/tm_gmtoff.>> z <- ISOdate(1890:1912, 1, 10, tz="UTC")> ## Rome changed to CET for 1894> as.POSIXlt(z, tz="Europe/Rome")[1] "1890-01-10 12:49:56 RMT" "1891-01-10 12:49:56 RMT"[3] "1892-01-10 12:49:56 RMT" "1893-01-10 12:49:56 RMT"[5] "1894-01-10 13:00:00 CET" "1895-01-10 13:00:00 CET"[7] "1896-01-10 13:00:00 CET" "1897-01-10 13:00:00 CET"[9] "1898-01-10 13:00:00 CET" "1899-01-10 13:00:00 CET"[11] "1900-01-10 13:00:00 CET" "1901-01-10 13:00:00 CET"[13] "1902-01-10 13:00:00 CET" "1903-01-10 13:00:00 CET"[15] "1904-01-10 13:00:00 CET" "1905-01-10 13:00:00 CET"[17] "1906-01-10 13:00:00 CET" "1907-01-10 13:00:00 CET"[19] "1908-01-10 13:00:00 CET" "1909-01-10 13:00:00 CET"[21] "1910-01-10 13:00:00 CET" "1911-01-10 13:00:00 CET"[23] "1912-01-10 13:00:00 CET"> ## Paris changed to PMT for 1892, WET for 1912> (zz <- as.POSIXlt(z, tz="Europe/Paris"))[1] "1890-01-10 12:09:21 LMT" "1891-01-10 12:09:21 LMT"[3] "1892-01-10 12:09:21 PMT" "1893-01-10 12:09:21 PMT"[5] "1894-01-10 12:09:21 PMT" "1895-01-10 12:09:21 PMT"[7] "1896-01-10 12:09:21 PMT" "1897-01-10 12:09:21 PMT"[9] "1898-01-10 12:09:21 PMT" "1899-01-10 12:09:21 PMT"[11] "1900-01-10 12:09:21 PMT" "1901-01-10 12:09:21 PMT"[13] "1902-01-10 12:09:21 PMT" "1903-01-10 12:09:21 PMT"[15] "1904-01-10 12:09:21 PMT" "1905-01-10 12:09:21 PMT"[17] "1906-01-10 12:09:21 PMT" "1907-01-10 12:09:21 PMT"[19] "1908-01-10 12:09:21 PMT" "1909-01-10 12:09:21 PMT"[21] "1910-01-10 12:09:21 PMT" "1911-01-10 12:09:21 PMT"[23] "1912-01-10 12:00:00 WET"> strftime(zz, "%Y-%m-%d %H:%M:%S %Z")[1] "1890-01-10 12:09:21 LMT" "1891-01-10 12:09:21 LMT"[3] "1892-01-10 12:09:21 PMT" "1893-01-10 12:09:21 PMT"[5] "1894-01-10 12:09:21 PMT" "1895-01-10 12:09:21 PMT"[7] "1896-01-10 12:09:21 PMT" "1897-01-10 12:09:21 PMT"[9] "1898-01-10 12:09:21 PMT" "1899-01-10 12:09:21 PMT"[11] "1900-01-10 12:09:21 PMT" "1901-01-10 12:09:21 PMT"[13] "1902-01-10 12:09:21 PMT" "1903-01-10 12:09:21 PMT"[15] "1904-01-10 12:09:21 PMT" "1905-01-10 12:09:21 PMT"[17] "1906-01-10 12:09:21 PMT" "1907-01-10 12:09:21 PMT"[19] "1908-01-10 12:09:21 PMT" "1909-01-10 12:09:21 PMT"[21] "1910-01-10 12:09:21 PMT" "1911-01-10 12:09:21 PMT"[23] "1912-01-10 12:00:00 WET"> ## The offset was really +00:09:21 until 1911, then +00:00> ## Many platforms will give the current offset, +0100> strftime(zz, "%Y-%m-%d %H:%M:%S %z")[1] "1890-01-10 12:09:21 +0009" "1891-01-10 12:09:21 +0009"[3] "1892-01-10 12:09:21 +0009" "1893-01-10 12:09:21 +0009"[5] "1894-01-10 12:09:21 +0009" "1895-01-10 12:09:21 +0009"[7] "1896-01-10 12:09:21 +0009" "1897-01-10 12:09:21 +0009"[9] "1898-01-10 12:09:21 +0009" "1899-01-10 12:09:21 +0009"[11] "1900-01-10 12:09:21 +0009" "1901-01-10 12:09:21 +0009"[13] "1902-01-10 12:09:21 +0009" "1903-01-10 12:09:21 +0009"[15] "1904-01-10 12:09:21 +0009" "1905-01-10 12:09:21 +0009"[17] "1906-01-10 12:09:21 +0009" "1907-01-10 12:09:21 +0009"[19] "1908-01-10 12:09:21 +0009" "1909-01-10 12:09:21 +0009"[21] "1910-01-10 12:09:21 +0009" "1911-01-10 12:09:21 +0009"[23] "1912-01-10 12:00:00 +0000">> ## Some platforms give details of the latest conversion.> z <- ISOdate(c(seq(1890, 1940, 5), 1941:1946, 1950), 1, 10, tz="UTC")> as.POSIXlt(z, tz="Europe/Paris")[1] "1890-01-10 12:09:21 LMT" "1895-01-10 12:09:21 PMT"[3] "1900-01-10 12:09:21 PMT" "1905-01-10 12:09:21 PMT"[5] "1910-01-10 12:09:21 PMT" "1915-01-10 12:00:00 WET"[7] "1920-01-10 12:00:00 WET" "1925-01-10 12:00:00 WET"[9] "1930-01-10 12:00:00 WET" "1935-01-10 12:00:00 WET"[11] "1940-01-10 12:00:00 WET" "1941-01-10 14:00:00 CEST"[13] "1942-01-10 14:00:00 CEST" "1943-01-10 13:00:00 CET"[15] "1944-01-10 13:00:00 CET" "1945-01-10 13:00:00 WEST"[17] "1946-01-10 13:00:00 CET" "1950-01-10 13:00:00 CET"> for(i in seq_along(z)) print(as.POSIXlt(z[i], tz="Europe/Paris"))[1] "1890-01-10 12:09:21 LMT"[1] "1895-01-10 12:09:21 PMT"[1] "1900-01-10 12:09:21 PMT"[1] "1905-01-10 12:09:21 PMT"[1] "1910-01-10 12:09:21 PMT"[1] "1915-01-10 12:00:00 WET"[1] "1920-01-10 12:00:00 WET"[1] "1925-01-10 12:00:00 WET"[1] "1930-01-10 12:00:00 WET"[1] "1935-01-10 12:00:00 WET"[1] "1940-01-10 12:00:00 WET"[1] "1941-01-10 14:00:00 CEST"[1] "1942-01-10 14:00:00 CEST"[1] "1943-01-10 13:00:00 CET"[1] "1944-01-10 13:00:00 CET"[1] "1945-01-10 13:00:00 WEST"[1] "1946-01-10 13:00:00 CET"[1] "1950-01-10 13:00:00 CET"> ## use pf %z needs tm_gmtoff> for(i in seq_along(z))+ print(strftime(as.POSIXlt(z[i], tz="Europe/Paris"), "%Y-%m-%d %H:%M:%S %z"))[1] "1890-01-10 12:09:21 +0009"[1] "1895-01-10 12:09:21 +0009"[1] "1900-01-10 12:09:21 +0009"[1] "1905-01-10 12:09:21 +0009"[1] "1910-01-10 12:09:21 +0009"[1] "1915-01-10 12:00:00 +0000"[1] "1920-01-10 12:00:00 +0000"[1] "1925-01-10 12:00:00 +0000"[1] "1930-01-10 12:00:00 +0000"[1] "1935-01-10 12:00:00 +0000"[1] "1940-01-10 12:00:00 +0000"[1] "1941-01-10 14:00:00 +0200"[1] "1942-01-10 14:00:00 +0200"[1] "1943-01-10 13:00:00 +0100"[1] "1944-01-10 13:00:00 +0100"[1] "1945-01-10 13:00:00 +0100"[1] "1946-01-10 13:00:00 +0100"[1] "1950-01-10 13:00:00 +0100">> strptime("1920-12-27 08:18:23", "%Y-%m-%d %H:%M:%S", tz="Europe/Paris")[1] "1920-12-27 08:18:23 WET">> ## check %V etc>> d <- expand.grid(day = 1:7, year = 2000:2010)> z1 <- with(d, ISOdate(year, 1, day))> d <- expand.grid(day = 25:31, year = 2000:2010)> z2 <- with(d, ISOdate(year, 12, day))> z <- sort(c(z1, z2))> strftime(z, "%G %g %W %U %u %V %W %w", tz="Europe/Paris")[1] "1999 99 00 00 6 52 00 6" "1999 99 00 01 7 52 00 0"[3] "2000 00 01 01 1 01 01 1" "2000 00 01 01 2 01 01 2"[5] "2000 00 01 01 3 01 01 3" "2000 00 01 01 4 01 01 4"[7] "2000 00 01 01 5 01 01 5" "2000 00 52 52 1 52 52 1"[9] "2000 00 52 52 2 52 52 2" "2000 00 52 52 3 52 52 3"[11] "2000 00 52 52 4 52 52 4" "2000 00 52 52 5 52 52 5"[13] "2000 00 52 52 6 52 52 6" "2000 00 52 53 7 52 52 0"[15] "2001 01 01 00 1 01 01 1" "2001 01 01 00 2 01 01 2"[17] "2001 01 01 00 3 01 01 3" "2001 01 01 00 4 01 01 4"[19] "2001 01 01 00 5 01 01 5" "2001 01 01 00 6 01 01 6"[21] "2001 01 01 01 7 01 01 0" "2001 01 52 51 2 52 52 2"[23] "2001 01 52 51 3 52 52 3" "2001 01 52 51 4 52 52 4"[25] "2001 01 52 51 5 52 52 5" "2001 01 52 51 6 52 52 6"[27] "2001 01 52 52 7 52 52 0" "2002 02 53 52 1 01 53 1"[29] "2002 02 00 00 2 01 00 2" "2002 02 00 00 3 01 00 3"[31] "2002 02 00 00 4 01 00 4" "2002 02 00 00 5 01 00 5"[33] "2002 02 00 00 6 01 00 6" "2002 02 00 01 7 01 00 0"[35] "2002 02 01 01 1 02 01 1" "2002 02 51 51 3 52 51 3"[37] "2002 02 51 51 4 52 51 4" "2002 02 51 51 5 52 51 5"[39] "2002 02 51 51 6 52 51 6" "2002 02 51 52 7 52 51 0"[41] "2003 03 52 52 1 01 52 1" "2003 03 52 52 2 01 52 2"[43] "2003 03 00 00 3 01 00 3" "2003 03 00 00 4 01 00 4"[45] "2003 03 00 00 5 01 00 5" "2003 03 00 00 6 01 00 6"[47] "2003 03 00 01 7 01 00 0" "2003 03 01 01 1 02 01 1"[49] "2003 03 01 01 2 02 01 2" "2003 03 51 51 4 52 51 4"[51] "2003 03 51 51 5 52 51 5" "2003 03 51 51 6 52 51 6"[53] "2003 03 51 52 7 52 51 0" "2004 04 52 52 1 01 52 1"[55] "2004 04 52 52 2 01 52 2" "2004 04 52 52 3 01 52 3"[57] "2004 04 00 00 4 01 00 4" "2004 04 00 00 5 01 00 5"[59] "2004 04 00 00 6 01 00 6" "2004 04 00 01 7 01 00 0"[61] "2004 04 01 01 1 02 01 1" "2004 04 01 01 2 02 01 2"[63] "2004 04 01 01 3 02 01 3" "2004 04 51 51 6 52 51 6"[65] "2004 04 51 52 7 52 51 0" "2004 04 52 52 1 53 52 1"[67] "2004 04 52 52 2 53 52 2" "2004 04 52 52 3 53 52 3"[69] "2004 04 52 52 4 53 52 4" "2004 04 52 52 5 53 52 5"[71] "2004 04 00 00 6 53 00 6" "2004 04 00 01 7 53 00 0"[73] "2005 05 01 01 1 01 01 1" "2005 05 01 01 2 01 01 2"[75] "2005 05 01 01 3 01 01 3" "2005 05 01 01 4 01 01 4"[77] "2005 05 01 01 5 01 01 5" "2005 05 51 52 7 51 51 0"[79] "2005 05 52 52 1 52 52 1" "2005 05 52 52 2 52 52 2"[81] "2005 05 52 52 3 52 52 3" "2005 05 52 52 4 52 52 4"[83] "2005 05 52 52 5 52 52 5" "2005 05 52 52 6 52 52 6"[85] "2005 05 00 01 7 52 00 0" "2006 06 01 01 1 01 01 1"[87] "2006 06 01 01 2 01 01 2" "2006 06 01 01 3 01 01 3"[89] "2006 06 01 01 4 01 01 4" "2006 06 01 01 5 01 01 5"[91] "2006 06 01 01 6 01 01 6" "2006 06 52 52 1 52 52 1"[93] "2006 06 52 52 2 52 52 2" "2006 06 52 52 3 52 52 3"[95] "2006 06 52 52 4 52 52 4" "2006 06 52 52 5 52 52 5"[97] "2006 06 52 52 6 52 52 6" "2006 06 52 53 7 52 52 0"[99] "2007 07 01 00 1 01 01 1" "2007 07 01 00 2 01 01 2"[101] "2007 07 01 00 3 01 01 3" "2007 07 01 00 4 01 01 4"[103] "2007 07 01 00 5 01 01 5" "2007 07 01 00 6 01 01 6"[105] "2007 07 01 01 7 01 01 0" "2007 07 52 51 2 52 52 2"[107] "2007 07 52 51 3 52 52 3" "2007 07 52 51 4 52 52 4"[109] "2007 07 52 51 5 52 52 5" "2007 07 52 51 6 52 52 6"[111] "2007 07 52 52 7 52 52 0" "2008 08 53 52 1 01 53 1"[113] "2008 08 00 00 2 01 00 2" "2008 08 00 00 3 01 00 3"[115] "2008 08 00 00 4 01 00 4" "2008 08 00 00 5 01 00 5"[117] "2008 08 00 00 6 01 00 6" "2008 08 00 01 7 01 00 0"[119] "2008 08 01 01 1 02 01 1" "2008 08 51 51 4 52 51 4"[121] "2008 08 51 51 5 52 51 5" "2008 08 51 51 6 52 51 6"[123] "2008 08 51 52 7 52 51 0" "2009 09 52 52 1 01 52 1"[125] "2009 09 52 52 2 01 52 2" "2009 09 52 52 3 01 52 3"[127] "2009 09 00 00 4 01 00 4" "2009 09 00 00 5 01 00 5"[129] "2009 09 00 00 6 01 00 6" "2009 09 00 01 7 01 00 0"[131] "2009 09 01 01 1 02 01 1" "2009 09 01 01 2 02 01 2"[133] "2009 09 01 01 3 02 01 3" "2009 09 51 51 5 52 51 5"[135] "2009 09 51 51 6 52 51 6" "2009 09 51 52 7 52 51 0"[137] "2009 09 52 52 1 53 52 1" "2009 09 52 52 2 53 52 2"[139] "2009 09 52 52 3 53 52 3" "2009 09 52 52 4 53 52 4"[141] "2009 09 00 00 5 53 00 5" "2009 09 00 00 6 53 00 6"[143] "2009 09 00 01 7 53 00 0" "2010 10 01 01 1 01 01 1"[145] "2010 10 01 01 2 01 01 2" "2010 10 01 01 3 01 01 3"[147] "2010 10 01 01 4 01 01 4" "2010 10 51 51 6 51 51 6"[149] "2010 10 51 52 7 51 51 0" "2010 10 52 52 1 52 52 1"[151] "2010 10 52 52 2 52 52 2" "2010 10 52 52 3 52 52 3"[153] "2010 10 52 52 4 52 52 4" "2010 10 52 52 5 52 52 5">> ## tests of earlier years. Default format is OS-dependent, so don't test it.> ## ISOdate only accepts positive years.> z <- as.Date(ISOdate(c(0, 8, 9, 10, 11, 20, 110, 1010), 1, 10)) - 3630> strftime(z, "%04Y-%m-%d") # with leading zero(s), where supported[1] "-010-02-01" "-002-02-01" "-001-02-02" "0000-02-02" "0001-02-01"[6] "0010-02-01" "0100-02-01" "1000-02-01"> strftime(z, "%_4Y-%m-%d") # with leading space(s), where supported[1] " -10-02-01" " -2-02-01" " -1-02-02" " 0-02-02" " 1-02-01"[6] " 10-02-01" " 100-02-01" "1000-02-01"> strftime(z, "%0Y-%m-%d") # without[1] "-10-02-01" "-2-02-01" "-1-02-02" "0-02-02" "1-02-01"[6] "10-02-01" "100-02-01" "1000-02-01">>> ## more test of strftime> x <- ISOdate(2014, 3, 10, c(7, 13))> fmts <- c("%Y-%m-%d %H:%M:%S", "%F", "%A %a %b %h %e %I %j",+ ## locale-dependent ones+ "%X", # but the same in all English locales+ "%c", "%x", "%p", "%r")> for (f in fmts) print(format(x, f))[1] "2014-03-10 07:00:00" "2014-03-10 13:00:00"[1] "2014-03-10" "2014-03-10"[1] "Monday Mon Mar Mar 10 07 069" "Monday Mon Mar Mar 10 01 069"[1] "07:00:00" "13:00:00"[1] "Mon Mar 10 07:00:00 2014" "Mon Mar 10 13:00:00 2014"[1] "03/10/14" "03/10/14"[1] "AM" "PM"[1] "07:00:00 AM" "01:00:00 PM">> ## Moved from reg-tests-1d.R> ## as.POSIXlt(<very large Date>) gave integer overflow> ## and needed C-level change for 32-bit time_t.> .Machine$sizeof.time_t[1] 8> (z <- .Date(2^31 + 10))[1] "5881580-07-22"> as.POSIXlt(z)$year == 5879680L[1] TRUE> ## year was negative in R <= 4.2.1, even for 64-bit time_t>>> ## ------------- Tests of far-distant dates -----------> Sys.setenv(TZ = "Europe/London")> ## the pre-1902 POSIXct values wil be 75s out on platdorm that do not> ## know about UK changes prior to 1902 (in fact in 1847-12-01: see below).> as.POSIXct("4000-07-01")[1] "4000-07-01 BST"> as.Date("4000-07-01")[1] "4000-07-01"> zz <- z <- as.POSIXlt("2000-07-01")> unclass(z)$sec[1] 0$min[1] 0$hour[1] 0$mday[1] 1$mon[1] 6$year[1] 100$wday[1] 6$yday[1] 182$isdst[1] 1$zone[1] "BST"$gmtoff[1] NAattr(,"tzone")[1] "Europe/London" "GMT" "BST"attr(,"balanced")[1] TRUE>> years <- c(-1e6, -1e5, -1e4, seq(-1000, 4000, by = 100), 1e4, 1e5, 1e6)> y <- character(length(years))> for(i in seq_along(years)) {+ zz$year = years[i] - 1900+ y[i] <- strftime(zz)+ }> y[1] "-1000000-07-01" "-100000-07-01" "-10000-07-01" "-1000-07-01"[5] "-900-07-01" "-800-07-01" "-700-07-01" "-600-07-01"[9] "-500-07-01" "-400-07-01" "-300-07-01" "-200-07-01"[13] "-100-07-01" "0000-07-01" "0100-07-01" "0200-07-01"[17] "0300-07-01" "0400-07-01" "0500-07-01" "0600-07-01"[21] "0700-07-01" "0800-07-01" "0900-07-01" "1000-07-01"[25] "1100-07-01" "1200-07-01" "1300-07-01" "1400-07-01"[29] "1500-07-01" "1600-07-01" "1700-07-01" "1800-07-01"[33] "1900-07-01" "2000-07-01" "2100-07-01" "2200-07-01"[37] "2300-07-01" "2400-07-01" "2500-07-01" "2600-07-01"[41] "2700-07-01" "2800-07-01" "2900-07-01" "3000-07-01"[45] "3100-07-01" "3200-07-01" "3300-07-01" "3400-07-01"[49] "3500-07-01" "3600-07-01" "3700-07-01" "3800-07-01"[53] "3900-07-01" "4000-07-01" "10000-07-01" "100000-07-01"[57] "1000000-07-01">> y <- double(length(years))> for(i in seq_along(years)) {+ zz$year = years[i] - 1900+ zz$isdst <- -1 # some are DST, some not so let the code decide+ y[i] <- as.POSIXct(zz)+ }> print(y, digits=14)[1] -31619103494325 -3217846694325 -377721014325 -93708489525[5] -90552815925 -87397055925 -84241382325 -81085708725[9] -77930035125 -74774275125 -71618601525 -68462927925[13] -65307254325 -62151494325 -58995820725 -55840147125[17] -52684473525 -49528713525 -46373039925 -43217366325[21] -40061692725 -36905932725 -33750259125 -30594585525[25] -27438911925 -24283151925 -21127478325 -17971804725[29] -14816131125 -11660371125 -8504697525 -5349023925[33] -2193350400 962406000 4118079600 7273753200[37] 10429426800 13585186800 16740860400 19896534000[41] 23052207600 26207967600 29363641200 32519314800[45] 35674988400 38830748400 41986422000 45142095600[49] 48297769200 51453529200 54609202800 57764876400[53] 60920550000 64076310000 253418022000 3093543702000[57] 31494800502000> y <- .POSIXct(y)> (y1 <- strftime(y)) # leading zeros or spaces is platform-dependant[1] "-1000000-07-01" "-100000-07-01" "-10000-07-01" "-1000-07-01"[5] "-900-07-01" "-800-07-01" "-700-07-01" "-600-07-01"[9] "-500-07-01" "-400-07-01" "-300-07-01" "-200-07-01"[13] "-100-07-01" "0000-07-01" "0100-07-01" "0200-07-01"[17] "0300-07-01" "0400-07-01" "0500-07-01" "0600-07-01"[21] "0700-07-01" "0800-07-01" "0900-07-01" "1000-07-01"[25] "1100-07-01" "1200-07-01" "1300-07-01" "1400-07-01"[29] "1500-07-01" "1600-07-01" "1700-07-01" "1800-07-01"[33] "1900-07-01" "2000-07-01" "2100-07-01" "2200-07-01"[37] "2300-07-01" "2400-07-01" "2500-07-01" "2600-07-01"[41] "2700-07-01" "2800-07-01" "2900-07-01" "3000-07-01"[45] "3100-07-01" "3200-07-01" "3300-07-01" "3400-07-01"[49] "3500-07-01" "3600-07-01" "3700-07-01" "3800-07-01"[53] "3900-07-01" "4000-07-01" "10000-07-01" "100000-07-01"[57] "1000000-07-01"> y2 <- strftime(y, "%_4Y-%m-%d") # not all platforms interpret this> if(y2[1] != "4Y-07-01") print(y2) else message('format "%_4Y" unsupported')[1] "-1000000-07-01" "-100000-07-01" "-10000-07-01" "-1000-07-01"[5] "-900-07-01" "-800-07-01" "-700-07-01" "-600-07-01"[9] "-500-07-01" "-400-07-01" "-300-07-01" "-200-07-01"[13] "-100-07-01" " 0-07-01" " 100-07-01" " 200-07-01"[17] " 300-07-01" " 400-07-01" " 500-07-01" " 600-07-01"[21] " 700-07-01" " 800-07-01" " 900-07-01" "1000-07-01"[25] "1100-07-01" "1200-07-01" "1300-07-01" "1400-07-01"[29] "1500-07-01" "1600-07-01" "1700-07-01" "1800-07-01"[33] "1900-07-01" "2000-07-01" "2100-07-01" "2200-07-01"[37] "2300-07-01" "2400-07-01" "2500-07-01" "2600-07-01"[41] "2700-07-01" "2800-07-01" "2900-07-01" "3000-07-01"[45] "3100-07-01" "3200-07-01" "3300-07-01" "3400-07-01"[49] "3500-07-01" "3600-07-01" "3700-07-01" "3800-07-01"[53] "3900-07-01" "4000-07-01" "10000-07-01" "100000-07-01"[57] "1000000-07-01">> y <- double(length(years))> for(i in seq_along(years)) {+ zz$year = years[i] - 1900+ zz$isdst <- -1+ y[i] <- as.Date(zz)+ }> y[1] -365961846 -37243596 -4371771 -1084589 -1048065 -1011540[7] -975016 -938492 -901968 -865443 -828919 -792395[13] -755871 -719346 -682822 -646298 -609774 -573249[19] -536725 -500201 -463677 -427152 -390628 -354104[25] -317580 -281055 -244531 -208007 -171483 -134958[31] -98434 -61910 -25386 11139 47663 84187[37] 120711 157236 193760 230284 266808 303333[43] 339857 376381 412905 449430 485954 522478[49] 559002 595527 632051 668575 705099 741624[55] 2933079 35804904 364523154> class(y) <- "Date"> (y3 <- strftime(y))[1] "-1000000-07-01" "-100000-07-01" "-10000-07-01" "-1000-07-01"[5] "-900-07-01" "-800-07-01" "-700-07-01" "-600-07-01"[9] "-500-07-01" "-400-07-01" "-300-07-01" "-200-07-01"[13] "-100-07-01" "0000-07-01" "0100-07-01" "0200-07-01"[17] "0300-07-01" "0400-07-01" "0500-07-01" "0600-07-01"[21] "0700-07-01" "0800-07-01" "0900-07-01" "1000-07-01"[25] "1100-07-01" "1200-07-01" "1300-07-01" "1400-07-01"[29] "1500-07-01" "1600-07-01" "1700-07-01" "1800-07-01"[33] "1900-07-01" "2000-07-01" "2100-07-01" "2200-07-01"[37] "2300-07-01" "2400-07-01" "2500-07-01" "2600-07-01"[41] "2700-07-01" "2800-07-01" "2900-07-01" "3000-07-01"[45] "3100-07-01" "3200-07-01" "3300-07-01" "3400-07-01"[49] "3500-07-01" "3600-07-01" "3700-07-01" "3800-07-01"[53] "3900-07-01" "4000-07-01" "10000-07-01" "100000-07-01"[57] "1000000-07-01"> y4 <- strftime(y, "%_4Y-%m-%d")> stopifnot(identical(y3, y1))>> zz <- as.POSIXlt("1900-07-01")> years <- c(1800, 1847:1848, 1899:1902)> y <- double(length(years))> for(i in seq_along(years)) {+ zz$year = years[i] - 1900+ zz$isdst <- -1 # some are DST, some not so let the code decide+ y[i] <- as.POSIXct(zz)+ }> print(y, digits=14)[1] -5349023925 -3865881525 -3834259200 -2224886400 -2193350400 -2161814400[7] -2130278400> .POSIXct(y)[1] "1800-07-01 LMT" "1847-07-01 LMT" "1848-07-01 GMT" "1899-07-01 GMT"[5] "1900-07-01 GMT" "1901-07-01 GMT" "1902-07-01 GMT">> ## change of 75s in 1847> seq(as.POSIXlt("1847-11-24"), as.POSIXlt("1847-12-07"), by ="day")[1] "1847-11-24 00:00:00 LMT" "1847-11-25 00:00:00 LMT"[3] "1847-11-26 00:00:00 LMT" "1847-11-27 00:00:00 LMT"[5] "1847-11-28 00:00:00 LMT" "1847-11-29 00:00:00 LMT"[7] "1847-11-30 00:00:00 LMT" "1847-12-01 00:01:15 GMT"[9] "1847-12-02 00:01:15 GMT" "1847-12-03 00:01:15 GMT"[11] "1847-12-04 00:01:15 GMT" "1847-12-05 00:01:15 GMT"[13] "1847-12-06 00:01:15 GMT">> ## end of ------------- Tests of far-distant dates ----------->> ## Tests of %z and %Z for output.> ## Use pf %z needs tm_gmtoff so offsets will otherwise be +0000> x1 <- strptime("2022-07-01", "%Y-%m-%d", tz = "UTC")> x2 <- strptime("2022-07-01", "%Y-%m-%d", tz = "Europe/Rome")> x1[1] "2022-07-01 UTC"> x2[1] "2022-07-01 CEST"> # RFC5322 format> format(x1, "%a, %d %b %Y %H:%M:%S %z")[1] "Fri, 01 Jul 2022 00:00:00 +0000"> # offset may not not determined: +0200 is correct> format(x2, "%a, %d %b %Y %H:%M:%S %z")[1] "Fri, 01 Jul 2022 00:00:00 +0200"> format(as.POSIXct(x2), "%a, %d %b %Y %H:%M:%S %z") # usually correct[1] "Fri, 01 Jul 2022 00:00:00 +0200"> format(x1, "%a, %d %b %Y %H:%M:%S %Z")[1] "Fri, 01 Jul 2022 00:00:00 UTC"> format(x2, "%a, %d %b %Y %H:%M:%S %Z")[1] "Fri, 01 Jul 2022 00:00:00 CEST">> ## offsets not in whole hours:> x3 <- strptime("2022-01-01", "%Y-%m-%d", tz = "Australia/Adelaide")> format(as.POSIXct(x3), "%a, %d %b %Y %H:%M:%S %z") # +10h30m[1] "Sat, 01 Jan 2022 00:00:00 +1030"> # macOS' strftime prints the next two wrong.> # Liberia does/did not have DST, so second abbreviation may be repeat or empty> x4 <- strptime("1971-01-01", "%Y-%m-%d", tz = "Africa/Monrovia")> y4 <- as.POSIXct(x4)> str(unclass(as.POSIXlt(y4))) # correct gmtoff, printed wrong on macOSList of 11$ sec : num 0$ min : int 0$ hour : int 0$ mday : int 1$ mon : int 0$ year : int 71$ wday : int 5$ yday : int 0$ isdst : int 0$ zone : chr "MMT"$ gmtoff: int -2670- attr(*, "tzone")= chr [1:3] "Africa/Monrovia" "GMT" " "- attr(*, "balanced")= logi TRUE> format(y4, "%a, %d %b %Y %H:%M:%S %z") # -44m, should be -00:44:30[1] "Fri, 01 Jan 1971 00:00:00 -0044"> ## timezones in 1900 might not be supported> x5 <- strptime("1900-03-01", "%Y-%m-%d", tz = "Europe/Paris")> y5 <- as.POSIXct(x5)> str(unclass(as.POSIXlt(y5))) # dittoList of 11$ sec : num 0$ min : int 0$ hour : int 0$ mday : int 1$ mon : int 2$ year : int 0$ wday : int 4$ yday : int 59$ isdst : int 0$ zone : chr "PMT"$ gmtoff: int 561- attr(*, "tzone")= chr [1:3] "Europe/Paris" "CET" "CEST"- attr(*, "balanced")= logi TRUE> format(y5, "%a, %d %b %Y %H:%M:%S %z")[1] "Thu, 01 Mar 1900 00:00:00 +0009">