similar to: Day or Month difference between dates???

Hi, I have data frame like this: Product Price Year_Month PE A 100 201012 -2 A 98 201101 -3 A 97 201102 -2.5 B 110 201101 -1 B 100 201102 -2 B 90 201103 -4 How can I achieve the following result

Folks, This question is somewhat related to a previous posting of mine. I just can't seem to create a generic solution. Here is a function that I found searching around the internet: splitIt <- function(x, n) {split(x, sort(rank(x) %% n))} I use it like so: > splitIt(1:12, 2) $`0` [1] 1 2 3 4 5 6 $`1` [1] 7 8 9 10 11 12 Or > splitIt(1:12, 4) $`0` [1] 1 2 3 $`1` [1] 4 5 6

HI, I have the following list: crosspries $crosspries[[1]] Product Year_Month prod1 A 201208 1 B 201208 2 C 201208 1 $crosspries[[2]] Product Year_Month prod1 prod2 A 201209 1 1 B 201209 2

HI, I have the pattern like "`Year_Month)201103`" I want to delete single quotes within double quetes. I want to change it into "Year_Month)201103" , how to do it in r? Thanks a lot. Tammy [[alternative HTML version deleted]]

HI, I have the price and volume data from own product and competitor's product: Year_Month Volume own product's price Volume competitor's price 1 201011 17583 469.03 NA NA 2 201012 33899 489.25 NA NA 3 201101 31306

Dear Gabor, Thanks for your reply. however: > tail(DJd) ^DJI.Close 2010-04-01 10927.07 2010-04-05 10973.55 2010-04-06 10969.99 2010-04-07 10897.52 2010-04-08 10927.07 *2010-04-09 10997.35* > tail(ag) 2009-11-30 10344.84 2009-12-31 10428.05 2010-01-31 10067.33 2010-02-28 10325.26 2010-03-31 10856.63 *2010-04-30 10997.35 * It seems the script "makes up"

Dear R Help, I am trying to get fields showing the last day of each month for a monthly closing project. In order to find the last day of the previous month, I subtract the number of days from the current month. For all months my code works; however, for October, my code doesn't work...it returns 2010-09-*29* instead of 2010-09-*30*. format(strptime("2010-10-31",

I have a vector that contains month and year in the format YYYYMM (e.g.“200701”, “200702”) I wish to do to things: 1. I need to convert to a date that is the last calendar day of each month. 2. I need to convert this to a date that is the last U.S. stock-exchange trading day of each month. Any advice is appreciated, mymonths <- c(200701, 200702)

Hi all, can anyone please guide me how to create a sequence of months? Here I have tried following however couldn't get success > library(zoo) > seq(as.yearmon("2010-01-01"), as.yearmon("2010-03-01"), by="1 month") Error in del/by : non-numeric argument to binary operator What is the correct way to do that? Thanks for your time.

Is there any R function to calculate automatically the last day of a particular month? For example "sep2009" should be converted to last day of September of 2009? Thanks -- View this message in context: http://www.nabble.com/How-to-get-last-day-of-a-month--tp25425645p25425645.html Sent from the R help mailing list archive at Nabble.com.

Hello! I have a data frame with dates. I need to create a new "month" that starts on the 20th of each month - because I'll need to aggregate my data later by that "shifted" month. I wrote the code below and it works. However, I was wondering if there is some ready-made function in some package - that makes it easier/more elegant? Thanks a lot! # Example data:

Hello, I would like to implement a "turn-of-the-month' trading strategy in R. Given a daily series of stock market return data as a zoo object, the strategy would go long (buy) four trading days before the end of the month, and sell the third trading day of the following month. How can I select these days, particularly the fourth day before and the third day after the turn of the

Hi, Given a date, how do I get the last date of that month? I have data in the form YYYYMM, that I've read as a date using > x$Date <- as.Date(ISOdate(substr(x$YearEnd,1,4),substr(x$YearEnd,5,6),1)) But this gives the first day of the month. To get the last day of the month, I tried > as.Date(as.yearmon(x$Date,frac=0)) But I don't get the last day of the month here. (Tried

Hello, I want to change the day of the month in a date object. What I am doing at the moment is: x=as.POSIXlt(x) x$mday=13 x=as.Date(x) Does anybody know if there is a more "natural" (eficient) way to do this Thank you Felipe Parra [[alternative HTML version deleted]]

I have a vector of dates. I wish to find the month end date for each. Any suggestions? e.g. For 12/15/05, I want 12/31/05, For 10/15/1995, I want 10/31/1995, etc __________________________________________________ [[alternative HTML version deleted]]

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

I'm quite new to R. I have a time series of annual state population estimates from census.gov, and I'd like to get a time series of monthly estimates, by a nonlinear interpolation. How can I do this in R? Thanks! [[alternative HTML version deleted]]

Dear R helpers. I am new to plotting time data using R. wonder how to convert character time info into date in R. I searched over the web but did not find answer. the input character string is something like 03_1993 or 03-1993, so the precision is at month level. I tried the following but failed. #R code below. strptime(c("03_1993"),"%m_%Y")

Dear R experts, I have a problem in modifying one column of a dataframe with a datatime format using a datetime operator. Here is my dataframe A: DATACONT PROVINCIA VALORE 1 2007-12-31 MI 1 2 2007-12-31 PV 2 3 2007-12-31 NA 3 4 2007-12-31 MI 4 5 2007-12-31 RM 5 6 2007-12-31 RM 6 7 2007-12-31 MI 7 8

Hi R users, Is there a function in R, which does some calculation only for the month end in a daily data?... In other words, is there a command in R, equivalent to "last." function in SAS? BR, Shubha [[alternative HTML version deleted]]