Hello, Thanks the Prof. Brian Ripley for his earlier response, however I still have a few issues with the times in R. I'd like to somehow set up R so it automatically has the timezone set to Western Australian standard time when I open up a workspace instead of Western Australian daylight savings time. Is this possible? I haven't had much luck in trying to find this. There are two main issues that I mentioned in my earlier email, in regards to the Oracle database I'm using the RODBC package to extract the data into R. I've tried using the newer version of RODBC (1.2-4) and the older version (1.2-3) of this package and I still get the NA values for the 2am and 2:30am datetime values for the start of daylight savings. However in R 2.6.2, I can use either version of RODBC without getting the error. The program is quite large, so I've just pickout the relevant bits of code needed to extract the data from Oracle >channel <<- odbcDriverConnect(paste("DSN=", dbdsn, ";UID=", dbuser, ";PWD=", dbpwd, sep=""), case="oracle") >total_cnsmptn_summary_vw<-sqlQuery(channel, paste("select INTERVAL_START_DATETIME, TOTAL_SMOOTHED_CNSMPTN_MWH+TOTAL_CHURN_MWH, NON_VEST_CNSMPTN_MWH+NON_VEST_CHURN_MWH, VEST_ISC_CNSMPTN_MWH+VEST_ISC_CHURN_MWH, TOTAL_SMOOTHED_CNSMPTN_MWH-NON_VEST_CNSMPTN_MWH-VEST_ISC_CNSMPTN_MWH+VEST_VC _CHURN_MWH from CONSUMPTION_SUMMARY where total_smoothed_cnsmptn_mwh > 0 and vest_isc_cnsmptn_mwh > 0 order by INTERVAL_START_DATETIME")) >names(total_cnsmptn_summary_vw)<-c('INTERVAL_START_DATETIME','TOTAL_SMOOTHE D_CNSMPTN_MWH','NON_VEST_CNSMPTN_MWH', 'VEST_ISC_CNSMPTN_MWH','VEST_VC_CNSMPTN_MWH') >total_cnsmptn_summary_vw[67735:67745,] INTERVAL_START_DATETIME TOTAL_SMOOTHED_CNSMPTN_MWH NON_VEST_CNSMPTN_MWH VEST_ISC_CNSMPTN_MWH VEST_VC_CNSMPTN_MWH 67735 2008-10-25 23:30:00 535.437 105.180 50.304 379.953 67736 2008-10-26 00:00:00 514.703 104.700 50.376 359.627 67737 2008-10-26 00:30:00 499.146 104.007 50.941 344.198 67738 2008-10-26 01:00:00 485.834 102.486 50.479 332.869 67739 2008-10-26 01:30:00 474.799 101.961 50.492 322.346 67740 <NA> 469.783 102.070 50.755 316.958 67741 <NA> 464.007 100.814 50.816 312.377 67742 2008-10-26 03:00:00 463.224 101.309 50.386 311.529 67743 2008-10-26 03:30:00 464.052 102.049 50.207 311.796 67744 2008-10-26 04:00:00 469.753 103.542 50.204 316.007 67745 2008-10-26 04:30:00 475.318 105.407 49.670 320.241 The second issue is the 2.8.1 version of R changing the times from a 2.6.2 workspace - this probably relates to the display setting, that mentioned (I think if I can set this to always use Western Australian standard time the problem will be fixed, but I am unsure as how to do this) I create a datetime object in R 2.6.2 and then load that workspace into 2.8.1 the time changes, In R 2.6.2 I've typed: >date1<-ISOdatetime(2008,1,1,8,00,00) >save.image("C:\\Data\\Profiles\\M063059\\Desktop\\test.RData") > date1 [1] "2008-01-01 08:00:00 W. Australia Standard Time" and then in R 2.8.1 I've typed > load("C:\\Data\\Profiles\\M063059\\Desktop\\test.RData") > date1 [1] "2008-01-01 09:00:00 WST" Kind Regards Rhiannon Rhiannon Marchant Forecasting Analyst Wholesale Synergy (ABN: 71 743 446 839), 228 Adelaide Tce, Perth, WA, 6000, Australia phone: (08) 6212 1464 | fax: (08) 6212 1036 | email: rhiannon.march...@synergy.net.au business enquiries: 131354 | identification no.: 300794 | website: [1]synergy.net.au Please consider the environment before printing this email.
Prof Brian Ripley <rip...@stats.ox.ac.uk> 27/02/2009 03:42 PM To Rhiannon Marchant <rhiannon.march...@synergy.net.au> cc r-help@r-project.org Subject Re: [R] removing daylight savings in R What do you mean by 'standard time'? If you mean UTC, set TZ=UTC. For anything else, see ?Sys.timezone (which explains the use of TZ). I am guessing that you are storing times in "POSIXct" objects (you do not say): they are in UTC. Have you any evidence that 'datetimes are getting converted to daylight savings times'? More likely they are getting *printed* in your local timezone, because that is the documented default behaviour. But you can change it (see ?format.POSIXct). You are attributing self-will to R in 'an ORACLE database that R is importing data in from': it is merely following instructions. We don't have those instructions and there is no sign of a package that could do this in your sessionInfo (R itself has no such facilities). If the Oracle database is not in your local timezone (which seems to be the case) you will need to tell the import facilty what time it is in. If the (non-R) import facility does this right, the datetimes will be marked as being in UTC (or whatever), and most of the time printed as such (but I would always do so explicitly). The difference betwee 2.6.2 and later versions is that lots of bugs in the way Windows handles timezones were fixed, so it sounds as if you have been relying on a Windows bug. On Fri, 27 Feb 2009, Rhiannon Marchant wrote: > > Hi all, > I've been having some trouble with times in regards to daylight savings in R > version 2.8.1. I have an ORACLE database that R is importing data in from, > for the 2am and 2:30am time intervals for the dates that daylight savings > starts the times are getting read as NA values into R. I'm also finding that > if I open a R workspace from version 6.2.2,the datetimes are getting > converted to daylight savings times. The times are a cruical part of my > analysis and need to stay in standard time. I would like to be using a newer > version of R than I am currently using (2.6.2) so that I can make use of the > newer packages that are available, however with this problem of the time > conversions I am unable to do this. Is anyone able to help with to set up > R2.8.1 to use standard time instead of daylight savings times? [...] -- Brian D. Ripley, rip...@stats.ox.ac.uk Professor of Applied Statistics, [2]http://www.stats.ox.ac.uk/~ripley/ University of Oxford, Tel: +44 1865 272861 (self) 1 South Parks Road, +44 1865 272866 (PA) Oxford OX1 3TG, UK Fax: +44 1865 272595 ======================================================================== SYNERGY. ABN 71 743 446 839, Perth, Western Australia. Telephone: +61 8 6212 2222 TO THE ADDRESSEE: Unencrypted E-mail is not secure and may not be authentic. We cannot guarantee the accuracy, reliability, completeness or confidentiality of this E-mail and any attachme nts ("E-Mail"). The e-mail system used for this communication is based on Western Standard T ime. Please check all times carefully if they are important to the context of the communication. IF YOU ARE NOT THE INTENDED ADDRESSEE: This E-Mail is intended solely forthe intended addressee and may be subject to legal or other professional privilege, or may contain information that is confidential or exempt from disclosure by law. Copying or distributing this E-Mail or any information it may contain, by anyone other than the intended addressee, is prohibited. If you have received this E-Mail in error please notify us immediately by return e-mail or by telephone; and destroy this E-Mail and any electronic or hard c opies of it. Any claim to privilege or confidentiality is not waived or lost by reason of mistaken transmission of this E-Mail. VIRUSES: Although we scan all outgoing e-mail and attachments for viruses, w e cannot guarantee that viruses will not be transmitted with this E-mail. It is the recipient's responsibility to che ck this E-Mail for viruses. ======================================================================== References 1. http://www.synergy.net.au/ 2. http://www.stats.ox.ac.uk/~ripley/ ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.