similar to: How to manipulate the time data without the date?

Hi,all: I am running a nonlinear regression and there is a problem. There is a data frame: data p s x t 1 875.0 12392.5 11600 0.06967213 2 615.0 12332.5 12000 0.06967213 3 595.0 12332.5 12000 0.06967213 4 592.5 12337.0 12000 0.06967213 5 650.0 12430.0 12000 0.06967213 6 715.0 12477.5 12000 0.06967213 . . . . str(data): 'data.frame': 234 obs. of 4 variables:

Dear R experts, How to find out the index of minimum or maxmum number in a vetor or data.frame? For example, a= n price 1 50 -2 100 0 200 -1 300 ...... I want to find out the row which the n is the smallest or largestest and extract the price. Thanks Ted -- View this message in context:

Dear all I am very intersted in writing my own function to deal with some complicated task, but I don't know how to start. I can't find detial material with examples teaching me how to write my own functions. Can anyone help me and recommend me some learning material? Many Thanks Ted -- View this message in context:

Dear R users I am runing into a problem in reading data in R This is the error information a<-read.table("tt_mb_200409.txt",as.is=T) Error in scan(file, what, nmax, sep, dec, quote, skip, nlines, na.strings, : line 1653997 did not have 5 elements It seams that some lines don't have equal variables. I want to try >

Hi all I have some tick-by-tick data and I have calculated the intraday returns. I want to sum up the intraday squared returns to calculate the daily volatility(or daily variance). I know that the s-plus FinMerics has the function aggregateSeries function that can be apply to daily data: aggregateSeries(x, Fun, by="daily"), but the counterpart function in R:applySeries can not be apply

Dear R experts, I have a folder names "200209" and in this folder there are many data files, such as: "BA020902.txt","BA020903.txt","BA020904.txt", "BA020905.txt","BA020906.txt","BA020909.txt", "BA020910.txt","BA020911.txt","BA020912.txt",

what package should I include to use timeDate? I want to convert a double (num of millis) into date object.

Hello, I was trying to import data from an Excel file. After I imported the data, I was trying to make a scatter plot. The X axes variable is a time variable, which occupies two columns, one is date, another one is time. Example 21-Apr-03, 4:10 PM. My qestion is: 1. How can I access the data of certain column? I mean how can I refer it in R? 2. How can I make the two column character

Hello, I am trying to use HMisc describe on a data frame. I have specified certain variables as dates using, for example: df1$aidsdate <- dates(aidsdate,format="day.mon.year", origin=c(month = 1, day = 1, year = 1960)) When I use describe on the dataframe I get this error: Error in Ops.dates(weights, x) : * not defined for chron objects Has anyone had this problem? I had

Dear R-helpers, In my data set, I have a time variable 'RecordTime' whose class property is 'times'. When I list my data set, I see the values of RecordTime is like 10:20:30 in a 'h:m:s' format. Suppose I want to choose all the data after 10 o'clock, then use subset(data,RecordTime>10:20:30) just doesn't work. I noticed that all the values of RecordTime seem

Hello! I am trying to identify which ones of a vector of dates are US holidays. And, ideally, which is which. And I do not know (a-priori) which dates those should be. I have, for example: x<-seq(as.Date("2011-01-01"),as.Date("2011-12-31"),by="day") (x) I think chron should help me here - but maybe I am not using it properly: library(chron) is.holiday(chron) #

note: whole function is below- I am sure I am doing something silly. when I use it like USGS(input="precipitation") it is choking on the precip.1 <- subset(DF, precipitation!="NA") b <- ddply(precip.1$precipitation, .(precip.1$gauge_name), cumsum) DF.precip <- precip.1 DF.precip$precipitation <- b$.data part, but runs fine outside of the function: days=7

Hello, today I've updated on the newest R-Version. But sadly a function I needed didnt want to work: The input is e.g. days(as.Date("21-07-2005","%d-%m-%y")) the error is: Fehler in Math.Date(dts): floor nicht definiert f??r Date Objekte (Error in Math.Date(dts): floor not defined for date objects) Same for year. Only months gives me the correct output. In Version

Full_Name: Zeng, zhenxing Version: 2.7.1 (2008-06-23) OS: windows XP Submission from: (NULL) (158.182.1.30) Dear Author I have run into a trouble in using chron package The data frame: a date time_fut expiry_day bid ask trade_day 1 2004-09-01 09:45:00 2004-10 12860 12889 38 2 2004-09-01 09:45:01 2004-10 12885 12890 38 3 2004-09-01 09:45:04 2004-10 12883 12887

Look at the bottom of the message for my question #here is a little function that I wrote USGS <- function(input="discharge", days=7){ library(chron) library(gsubfn) #021973269 is the Waynesboro Gauge on the Savannah River Proper (SRS) #02102908 is the Flat Creek Gauge (ftbrfcms) #02133500 is the Drowning Creek (ftbrbmcm) #02341800 is the Upatoi Creek Near Columbus (ftbn) #02342500 is

I'm reading in ~3 years worth of data that includes hourly timestamps. Presumably to avoid DST confusion, all the data is in PST time zone -- no discontinuities in the spring or fall. The data comes in a csv file, which I'm reading with myvariable <- read.csv("my_data_file.csv",header=FALSE,

Hello, I gather variants of this question have been asked previously. I have done some reading but only became more confused, as I suspect what I am trying to do is more basic than other applications. The following code readily calculates the difference in days between two dates: newdays <- ISOdate(2005, 5,12) - ISOdate(2006, 12, 22) However, I wanted to be able to deduct the dates in

summary: The function 'by' inconsistently strips class from the data to which it is applied. quick reason: tapply strips class when simplify is set to TRUE (the default) due to the class stripping behaviour of unlist. quick answer: This can be fixed by invoking tapply with simplify=FALSE, or changing tapply to use do.call(c instead of unlist executable example:

Not sure if there is an R way to do this or a regular express way, but here is what I am trying to do. I've got lots of data where the format is HH:MM:SS, but I need to format it like HH:MM:00, i.e. round the second down to zero. What is the best way to do this? Thanks again. Jason

Hello, I have large zoo objects (about 100 or more time series merged next to eachother). Example: X05.Oct.99 X05.Nov.99 X05.Dec.99 X05.Jan.00 X05.Feb.00 X05.Mar.00 X05.Apr.00 X05.May.00 X05.Jun.00 [1,] 5649.3 5679.4 5679.4 5679.4 5679.4 5679.4 5679.4 5679.4 5679.4 [2,] 5682.7 5719.2 5719.2 5719.2 5719.2 5719.2 5719.2