similar to: date and time

Dear R-user, I have read a dataset from .csv file into R. This dataset includes one column containing some data in 'date and time' format, e.g. 'dd/mm/yyyy hh:mm'. These data were automatically read and saved as 'factor' in R. When I was trying to produce some plots (such as time series) with the above 'date and time' on x-axis, it caused some disodering problem,

Hello all, I have a quick question about formatting date strings.. I am currently debugging some Matlab code someone else wrote and since it is so bad that I have to go through it line by line I figured that I would just rewrite the thing in R. The code produces plots of wave spectra with decimal days since the Epoch as the x axis and wave period as the Y axis. I am able to convert the date

There is something wrong, I think, with the date-time conversion from a numeric value if you use Central European Time (CET) as timezone. Examples from R: If I use the GMT time zone it is OK, I get the same time back from as.POSIXct as I entered > as.POSIXct(as.numeric(strptime("30/01/2012 13:00:00", format="%d/%m/%Y >

Dear List, This is my first post, and I'm a relatively new R user trying to work out a mixed effects model using lme() with random effects, and a correlation structure, and have looked over the archives, & R help on lme, corClasses, & etc extensively for clues. My programming experience is minimal (1 semester of C). My mentor, who has much more programming experience, but a comparable

Hi, when ploting Kaplan-Meier estimate curves as below, the censoring symbols (crosses) to not change thickness along the lines plot(survfit(surv ~ I(x>=cut.off) ),lty=c(1,2), lwd=2) is there any strightforward way to make it happen? thanks robert -- View this message in context: http://r.789695.n4.nabble.com/censoring-symbols-on-survfit-plot-tp3311283p3311283.html Sent from the R help

Hi, I am converting a data.frame to xts. ?the data.frame is 4 columns and 1000 rows. ?I get a message that "NROW (x) must match length(order.by) class is data.frame, mode is list when I run? dim(x) ? # I get? 1000 ? ? 4 ? #which is consistent with 1000 rows and 4 columns NROW (x) ?# I get 1000 ?# which is the right answer ? When I run length on each of columns in x separately using the

I have some time data and which is in seconds time <-c( 126230400 126252000 126273600 126295200 126316800 126338400) now I wanted to convert this time to Y M D H M S format I have tried following codes but it does not give me the out put in Y M D H M S time_t1 <- as.POSIXlt(time, origin="2005-01-01", tz="GMT") & time_f <- as.POSIXct(time,

Hello, I have strings with date-/time-data from a logfile. For a sort-by-time (and other time-related analysis) I need something to convert the times to the Unix-epoche-time (better also with parts of seconds). Is there something that does that job (or a similar conversion) in R? TIA, Oliver Bandel

Hello, This is mostly to developers, but in case I missed something in my literature search, I am sending this to the broader audience. - Are there any plans in the works to make "time" classes a bit more friendly to the rest of the "R" world? I am not suggesting to allow for fancy functions to manipulate times, per se, or to figure out how to properly

Hello, This is mostly to developers, but in case I missed something in my literature search, I am sending this to the broader audience. - Are there any plans in the works to make "time" classes a bit more friendly to the rest of the "R" world? I am not suggesting to allow for fancy functions to manipulate times, per se, or to figure out how to properly

Dear R useres, got the following problem. Given the AggData (listed below) I need to plot AggData[,2] vs time (AggData[,1]) for chosen 'rows'. Ive done already: plot(AggData[rows,2], xaxt='n') axis(1,at=seq(1,length(rows),1),sub("","", AggData[rows,1])) which works, but I need to list only chosen data points, say full hours or every 60th point, something like:

I used quantmod to pull in price data from the ticker SPY. The data has date and closing price. I would like to show the day of the week for each closing price. Is that possible? Also, I would like to add the back into the data frame in a new column without changing the structure of the data set if possible. SPY 2009-01-02 92.96 2009-01-05 92.85 2009-01-06 93.47

Hellos, I have date/times in 64-bit Julian format, that is the number of milliseconds since 1 jan 1970 (or something like that). E.g., "1159884877406" For the life of me I can't figure out how to render these in a more readable format, e.g., "2006-10-04 23:12:93.191" (and I have tried to do my best searching the archives and help etc ...) Thank you most

I have a data file where each entry is indexed by the time in seconds since epoch (e.g. 1046315697). Is there an easy way to convert this time value into a more friendly time (such as Month-Year) when plotting it? I searched through the manual, mailing lists, and functions like as.POSIXct and strptime, but didn't find what I need. Thanks, Sharad.

Hello, ? I have to create a new column from the values of other columns of a data frame. The new?column (y$n) is created imposing a condition (using a third variable y$h) that assigns the values of two time variables (y$b and y$timepos). Here's the piece of code to get there (using the attached files): ? xact <- read.table("act.lig", sep = ',',

Dear all I have a simple problem which I thought is easy to solve but what I tried did not work. I want to change character variables to factor in data frame. It goes easily from factor to character, but I am stuck in how to do backwards conversion. Here is an example irisf<-iris irisf[,2]<-factor(irisf[,2]) # create second factor str(irisf) 'data.frame': 150 obs. of 5

Hi, I have a process (not in R) that records events with a time stamp. So, I have a huge series of maybe 100,000 time stamps. I'd like to break it up into hourly (Or daily) intervals and then count how many events occurred in each interval. That way I can graph it. Ideally, converting the this into a time series in R would let me do some interesting analysis. The data is just a list of

Hola a todos: Debe de ser una tontería, pero no consigo saber porque la siguiente linea no devuelve la fecha actual: as.Date(as.numeric(Sys.time())) He hecho esa prueba porque no consigo pasar un numero convertido a partir de una fecha y modificado a fecha de nuevo. Gracias por adelantado. Un saludo, Alberto. [[alternative HTML version deleted]]

I read enourmous comment about this questions stating that it was answered before.? I?have been looking for the answer for a week without luck !!!? I searched the archives the xts. vignitte , googled for an answer but couldn't find one so her it is: ? the Vignette states that xts "doesn't inforce the duplicate row requirement" but yet when I try to bring in tick stock data from

Hi, I have some dates that are giving me a problem, in general the dates look like this: free.dates[60:61] [1] "2009-05-21 23:45:00 GMT" "2009-05-22 00:00:00 GMT" but for some reason, when taken "alone", they look like this: free.dates[60] [1] "2009-05-21 23:45:00 GMT" free.dates[61] [1] "2009-05-22 GMT" # the time component is gone, and