similar to: Regular time series with irregular start and end dates

Displaying 20 results from an estimated 2000 matches similar to: "Regular time series with irregular start and end dates"

2011 Sep 22
2
Subsetting a zooreg object using window / subset
Dear R users, I am currently working in subsetting a zooreg() object using either window or subset. I have a solution but it may be a bit cumbersome when I start working with actual data. Your inputs would be greatly appreciated. Example: I have a zooreg() object that starts in 1997 and ends in 2001. This object contains daily data for the 4 years
2005 Aug 27
2
zoo, zooreg, & ISOdatetime
I create a zooreg object that runs from Jan-1-2002 0:00 to Jun-1-2005 0:00... regts.start = ISOdatetime(2002, 1, 1, hour=0, min=0, sec=0, tz="") regts.end = ISOdatetime(2005, 6, 1, hour=0, min=0, sec=0, tz="") regts.zoo <- zooreg( NA, regts.start, regts.end, deltat=3600 ) Upon inspection: > regts.zoo[1:3] 2002-01-01 00:00:00 2002-01-01 01:00:00 2002-01-01 02:00:00
2012 Nov 25
2
creation of an high frequency series
Hi R Users! I would like to create an high frequency series but I am experiencing some difficulties. My series should start at 09.30 a.m. each day and end at 16.00 for, let's say, 2 years. I don't care on how many observations are for each day. It's ok also one observation each minute. In this case, I would have 390 observations each day. I have tried the following: start <-
2009 Apr 02
1
Time series analysis with irregular time-series
Dear R users I am currently investigating time series analysis using an irregular time series. Our study is looking at vegetation change in areas of alien vegetation growth after clearing events. The irregular time series is sourced from Landsat ETM+ data, over a six year period I have 38 scenes. For certain periods I have monthly data while for others, images are up to three months apart. So far
2005 Aug 27
1
ARIMA (seasonal) backcasting & interpolation
Thanks for everyone's help with zoo -- I think I've got my data set ready. (The data consists of surface weather temperatures, from 2002 to 2005, one observation per hour. Some values are missing... i.e. NA) I have three goals: GOAL #1:Get the data in proper time series form, preserving frequency information: > w4.ts <- as.ts( w3.zoo, frequency=(1/3600) ) I hope that 1/3600
2011 Feb 16
1
Timeseries Data Plotted as Monthly Boxplots
Hello, I'm trying to develop a box plot of time series data to look at the range in the data values over the entire period of record. My data initially starts out as a list of hourly data, and then I've been using this code to make this data into the final ts array. # Read in the station list stn.list <- read.csv("/home/kbennett/fews/stnlist3", as.is=T, header=F) # Read in
2005 Oct 25
2
strptime problem for 2004-10-03 02:00:00
Hello, I at first thought this was a system or locale issue, but since it occurs on both Windows and Linux and only for 2004 (AFAIK) I report it. I have a problem with as.POSIXct for the hour between "2004-10-03 02:00:00 GMT" and "2004-10-03 02:59:59 GMT". In short, the 2 AM (GMT) hour in 2004 (but not in other years) is interpreted as 1 AM by strptime: (I use ISOdatetime
2009 Jan 19
1
maptools, sunriset, POSIX timezones
Hi ... I wonder if anyone can provide some insight into why the first three examples using the sunriset function (appended below, with results) give the correct answer, but the fourth generates and error. The first two use ISOdatetime with and without a time zone attribute, and the sunriset function returns the correct sunset time. The third and fourth adds 10 seconds to the ISOdatetime
2008 Aug 20
1
pdf filenames in while loop
Dear R users, I am a remote sensing researcher currently studying the use of LiDAR data for quantifying tree height, in particular I would like to determine the sample size needed to capture and quantify canopy height variability. To do this I have employed the use of automap(), which automatically calculates variograms including reporting the range of the variogram. The program is easy to use
2008 Jan 10
2
how to calculate time offset between timezones?
#QUESTION# Is there a way to calculate the offset between timezones, e.g. from "AST" to "GMT"? #DETAILS# I am working with data files that use local time, and that indicate the timezone by e.g. "AST" (Atlantic Standard Time, my local time) in a header. I was guessing that > ISOdatetime(2008,1,1,1,0,0,tz="GMT") - >
2012 Jan 20
2
Incorrect DateTime using ISOdatetime in R
Dear list, I need to transform the DateTime of my GPS data from: "666.1751" into "yyyy/mm/dd hh:mm:ss" I have the following code: d$Date <- ISOdatetime(2009, 1, 1, 0, 0, 0, tz = "GMT")+d$Date*(24*3600) This gives me: 2010-10-29 04:12:09, which is wrong. It should be 2010-10-29 06:12:09 Another example: 418.3219 corresponds to: 2010-02-23 07:43:30, but it
2009 Feb 10
2
Strange behaviour of ISOdatetime
Hi All, I am watching a strange behaviour of ISOdatetime. In my work computer, I get NA when I try to do > ISOdatetime(1995,03,26,2,0,0) [1] NA But on other dates and/or times (hour) works OK > ISOdatetime(1995,03,25,2,0,0) [1] "1995-03-25 02:00:00 GMT" In my home computer, I do not have this problem. I am running the same version of R (2.8.1 patched) on both machines, the
2009 Feb 10
3
ISOdatetime gives NA for a specific date
Hi all, I am using ISOdatetime, and I just found out that when I do ISOdatetime(1995,03,26,2,10,0) (or any other value under minutes or seconds) I get NA This does not happen with the same time in other dates, nor with different hours in the same date. Any hint why this happens? Using R 2.8.1 under ESS/GnuEmacs under Windows XP Pedro -- View this message in context:
2011 Dec 14
1
A Question Re ISOdatetime
Dear all, I am using the ISOdatetime function like this: test.info$TradeTime = with(test.info, mapply(FUN = ISOdatetime, Year, Month, Day, Hour, Minute, 60, "EST")) Where Year, Month etc are all numeric. I think ISOdatetime should return a POSIXct object. However, the result I obtained from the line above is all numeric. Could you please advise? I wish to get POSIXct. Thank you
2012 Jul 19
1
as.POSIXct questions
The following three calls all produce the same result (my machine is in EST): > as.POSIXct(0, tz="", origin=ISOdatetime(1970,1,1,10,0,0)) [1] "1970-01-01 10:00:00 EST" > as.POSIXct(0, tz="EST", origin=ISOdatetime(1970,1,1,10,0,0)) [1] "1970-01-01 10:00:00 EST" > as.POSIXct(0, tz="GMT", origin=ISOdatetime(1970,1,1,10,0,0)) [1]
2004 Apr 29
1
Entering times around the start of daylight savings time
I'm having problems entering dates and times around when daylight savings time starts. If I type (on R 1.8.1 on Gentoo Linux) > ISOdatetime(2004,4,4,0:4,0,0,"GMT") [1] "2004-04-03 19:00:00 EST" "2004-04-03 20:00:00 EST" [3] "2004-04-03 22:00:00 EST" "2004-04-03 22:00:00 EST" [5] "2004-04-03 23:00:00 EST" Giving the times
2009 Jul 24
1
adjusting grid on Xaxis ticks
Hello, I have been trying to plot correctly a graph for 2 month now, with no success.I want to put a grid, adjusted on the X axis tickers. Here is the way I build my X-Axis and my grid: grid(11, NULL, col="grey40") axis(2) # build the tickers on the beginning of each monthticks.at <- seq(ISOdatetime(lastYear, 01, 01, hour=0, min=0, sec=0, tz="GMT"),
2011 Aug 05
3
excel dates and times in R
Hello, I am having some fun dealing with dates and times. My input is a excel csv file with two columns with data in the following format: date time 25-Jun-1961 04:00:00 i.e. day - month - year hour:min:sec I would like to have a single object in R that combines these and converts them into a sensible R format (e.g.
2007 Oct 09
1
Read in date fomat while colClasses="character"
Hi R users, I am using xlsReadWrite to read a particular excel file. In one of the columns I have dates ( say col=5). Now date column is read by default as numeric. So I used dateTimeAs= "isodatetime". This enables reading in the date format. However in the earlier column (say col=1) I have data which however starts from row 10. So to read data from column one I use
2002 Apr 08
1
Problem(?) in strptime()
I think the following examples illustrate the crux of the matter (version and OS info are below). The problem has to do with the transition from standard time to daylight savings time. My timezone, US/Pacific, has two parts: standard time (PST) 8 hours behind GMT and daylight savings time (PDT) 7 hours behind GMT. The transition takes place this year on 7 April at 02:00, when 02:00 is