similar to: Coercing a dataframe column to datetime

I am using 'read.csv' in V2.0.1 to read in a CSV file with the colClasses option and am getting an error from 'scan' when it encounters a non-numeric value for a 'numeric' column, i.e. > ds <- read.csv(in_file, nrows=irow, row.names=NULL, colClasses=zclass, comment.char="") Error in scan(file = file, what = what, sep = sep, quote =

I am stuck on trying to get the Lattice xyplot to output a separate PNG file each time through my 'for' loop. The files get produced but are empty. Here is the code. I'm running 1.9 on Windows. BTW is there a more efficient way of creating the separate output files than looping over the levels and subsetting? ......................................................... lev <-

I need to make plots similar to those produced by the s-plus rayplot function but can't seem to find it in R. These 'vector maps' plot a ray or vector at each specified location. Is there something similar in R ? --Rich Richard Kittler AMD TDG 408-749-4099

Does the 'groups' option on qqmath just color the points differently in the main distribution or does it actually overlay separate quantile plots for each subset? I would like to be able to do the latter. --Rich Richard Kittler AMD TDG 408-749-4099

Hi, I have a dataframe column of the form v<-c("Fri Feb 05 20:00:01.43000 2010","Fri Feb 05 20:00:02.274000 2010","Fri Feb 05 20:00:02.274000 2010","Fri Feb 05 20:00:06.34000 2010") I need to convert this to datetime form. I did the following.. lapply(v,function(x){strptime(x, "%a %b %d %H:%M:%OS %Y")}) This gives me a list that looks like

I've run into a problem with the datetime axis generated by axis.POSIXct. It appears a similar issue was discussed in October 2003 under the subject line "datetime data and plotting" (see https://stat.ethz.ch/pipermail/r-help/2003-October/039071.html), but I wasn't able to determine whether there is a straightforward solution. The code below produces a graph with apparently

Overall goal: I'd like to have a visual representation of when certain computer applications are running over the course of a day (data will come from a SQL query later, but I'm using a csv for now). My idea is to use a gantt chart, but I'm running into issues with the start and end time. I'm wondering if it's because I need to use hours instead of days as my unit of time.

Hello, i would like to import this txt file: Giorno;PM10 2006-01-01 10:10;10.3 2006-02-02 20:22;50.3 2006-03-03 23:33;20.1 ......... As it's an irregular time series i use zoo as follow: require(zoo) z <- read.table("c:\\1.csv", sep=";", na.strings="-999", header=TRUE) q <- zoo(z$PM10, strptime(as.character(z$Giorno),"%Y-%m-%d %H:%M")) At this

I am trying to use POSIX datetime objects rather than chron datetime objects but am having difficulty with POSIX in a time series. My question: Once a POSIXct vector is bound to a time series, is there a function to convert back to POSIXct? The following code demonstrates what I am trying to do. > ts(as.POSIXct(strptime(tmp,"%m/%d/%Y %H:%M:%S")),freq=1440) Time Series: Start =

hi, Index: leap_second/src/library/base/R/zdatetime.R =================================================================== --- leap_second/src/library/base/R/zdatetime.R (revision 68608) +++ leap_second/src/library/base/R/zdatetime.R (working copy) @@ -24,7 +24,8 @@ "1979-12-31", "1981-6-30", "1982-6-30", "1983-6-30",

If I take the following simple data: YEAR MONTH DAY WEIGHT.KG 2003 10 6 1.2 2003 10 12 1.2 2003 10 16 1.3 and format the date data and plot it: dates <- strptime(paste(DAY,MONTH,YEAR),"%d%m%Y") plot(c(min(dates),max(dates)),c(0,max(WEIGHT.KG)), xlab="Date",ylab="Weight (kg)",type="n") lines(dates,WEIGHT.KG) points(dates,WEIGHT.KG) I find that the

A newbie here - please forgive me if this is a basic question. We have an in house package built in R 2.2.1 (yes we're a little behind the times at our firm)and would like to rebuild it using R 2.5.1. However, when I try and build the package from source, I keep getting this error: Error in as(slotVal, slotClass, strict = FALSE) : no method or default for coercing "POSIXt"

Date-Time-Stamp input method to correctly interpret user-specific formats:coding is 90% there - based on exmple at http://tolstoy.newcastle.edu.au/R/help/05/02/12003.html ...anyone got the last 10% please? CONTEXT: Data is received where one of the columns is a datetimestamp. At midnight, the value represented as text in this column consists of just the date part, e.g.

Dear R Community, I am new to R, and have a question that I suspect may be quite simple but is proving a formidable roadblock for me. I have a large data set that includes water-quality measurements collected over many 24-hour periods. The date and time of sample collection are in a combined Date/Time field in the format yyyy-mm-dd hh:mm:ss. I need to be able to subset the data for analysis of

Greetings - I'm battling POSIXct, as per the code below. My input is actually an XL file, but the weird results below correctly model what I am seeing in my program. Before I punt and use lubridate or timeDate, could anyone please help me understand why POSIXct forces my variable back to GMT? I suspect that I'm not properly coding the tzone value, but it does not throw an

Dear R-Users, I have a data file with timestamps and I wanted to use POSIXct time data type to represent the respective column. I played around with the type and found a couple of issues: * there seems to be no direct way of reading datetimes into a variable. Let's say this is my file "1992-02-27 23:03:20 PST" "1992-02-27 22:29:56 PST" "1992-01-14 01:03:30 PST"

I've been using the following code to plot using Sweave in version 1.9.1 library(RODBC) library(lattice) channel <-odbcConnectExcel("h:/water.xls") data <- sqlQuery(channel,"select * from `Sheet1$` where Test = 'TOC' and (Valve='5010-05' or Valve='8030-V26' or Valve='1180-08' or Valve='5040-08')") odbcClose(channel) srt <-

Hi, I have a whole bunch of data, which looks like: 15/03/2003 10:20 1 15/03/2003 10:21 0 15/03/2003 12:02 0 16/03/2003 06:10 0 16/03/2003 06:20 0.5 16/03/2003 06:30 0 16/03/2003 06:40 0 16/03/2003 06:50 0 18/03/2003 20:10 0.5 etc. (times given on a 24 hour clock) and goes on for years. I have some code:

I'm relatively new to R .I tried converting the datetime column with values like 01apr1985:00:00:00.000 using strptime(datetime,"%d%b%Y).Could anyone help me in this regard .Please reply ASAP i need . -- View this message in context: http://www.nabble.com/Datetime-conversion-tp25503138p25503138.html Sent from the R help mailing list archive at Nabble.com.

Hi, Using the following simple character vector representing a time series with fractional seconds: datetime <- c("20/09/2011 13:00:59.00", "20/09/2011 13:00:59.02", "20/09/2011 13:00:59.04") Conversion to POSIXct runs into problems; the second element is not interpreted correctly: ---<--------------------cut