similar to: Convert date/time string to date

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,

I am trying to write some code where the factor references its previous value, but can't find a solution searching through the archive. > X first second 1 A 1 2 A 2 3 B 3 4 B 4 5 B 5 6 C 6 7 C 7 I need a third column, in pseudo code- If value of first=previous value of first: third=previous value of third else third =

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")

I a have a text file where every line is like that: "2007-12-03 13:50:17 Juan Perez" ("yy-mm-dd hh:mm:ss First Name Second Name") I would like to make a data frame with two column one for date and the other one for name. When I use read.delim it was transformed in a data frame with 4 colums. Bye, Sebasti?n.

Hello, Please excuse me if this question has been asked before. I'm new to R, and have been trying to google the answers without any success. I would like to convert a set of date and time into R date-time class. Right now, the dates and times are in integer format, so I first need to convert them into string, and then to R date-time using strptime. However, I have a problem converting them

Hello all, I'm hoping to convert a decimal value for week of the year back to a date object. Eg: strptime(paste(2010,1:52,sep=" "),format="%Y %W") I expected (hoped?) this would give me the date for Monday of each week. Instead, it's giving me 52 values of today's date. Where am I erring? Thanks Michael _______________________________________________________

Hi, I'm on my very first steps to R and so I hope that I do not ask a really stupid questions but I did not found it via R-Search, in the FAQ or Google (BTW, the name "R" is not a really good seekiong criterion ;-) ). I have a data file containing a table that containes dates and values like date\t value1\t value2, ... 01.03.2007\t 17\t 42\t ... 02.03.2007\t 2\t 3\t ...

Hello r-experts, I sure could us a little help. I have an ever updating text file with timestamped data in it. I can reformat in anyway I want if need be but currently I have chosen to make columns of date, time and measuresed value (comma delimeted and with the dates and times in quotes to interpret them as strings). Here is a small section of my text data file:

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

Hello, I have a date in the format Year-Month Name (e.g. 1990-January) and R classes it as a character. I want to convert this character into a date format, but when I try as.Date(1990-January, "%Y-%B"), I get back NA. The function strptime also gives me NA back. Thanks. [[alternative HTML version deleted]]

Hello, I have some "stupid" problems managing "date" data. I have a colomn "date", which I converted from a character representation: for example: a="26/02/06" date=strptime(a,format="%d/%m/%y") For one part of the analysis, I'm interested only in the month and the year, so I did: m.y=strftime(date,format="%m/%y") This returns me

I've got an array of times in H:MM:SS PM/AM format, e.g. "5:27:15 PM" (no leading zero), and I would like to convert them over to 24 HR syntax, e.g. HH:MM:SS. If it matters, the times are from the Central Time zone. Is there a command to convert the time to a 24HR format? I tried the following: ptime("5:27:15 PM", "%H:%M:%S") [1] "2009-11-04

I have a text (csv) file) with two columns: dates and numeric measurements. I read it using read.table and the dates get read as a factor, with as many levels as there are dates in the data. How can I create a matrix-like data structure (data frame?) which has one column of “real” dates (a vector of dates, not a factor variable) and one column of the numeric measurements? The strptime function

I'm stuck, but am sure it can be done I just don't understand how. I have data in an irregular timeseries. I want to be able to use stl to visualise the data (see seasonal parts etc), so I need to change to regular series of class ts (I think). I am using 2 zoo objects one is regular and the other is my irregular data. I am then merging to create the object I want but when I try to change

I have some data that includes timestamps like this: 2017-02-28T13:35:00+03:00 The documentation for strptime says that %z expects an offset like 0300. I don't see any way in the documentation to get it to accept +hh:mm with a colon separator, and everything I tried gave me NA as the answer. Section 4.2.5.1 of ISO 8601:2004(E) allows both the absence of colons in +hh[mm] (basic format) and

R offers a bewildering array of options when it comes to representing dates and times (e.g, as.Date, chron, strptime, zoo, etc). Can anybody recommend a document that compares the relative merit of each method? I'm not looking for help with any one method, but rather a guide that describes which method is best for a particular data analysis/plotting goal. Thanks, Jake [[alternative

Dear all, I have a date related question. Suppose I have a character string "March-2009", how I can convert it to a valid date object like as.yearmon("2009-01-03") in the zoo package? Is there any possibility there? Ans secondly is there any R function which will give the names of of all months as "LETTERS" does? Thanks for your time. [[alternative HTML version

I thought this is a common question but rseek/google searches don't yield any relevant hit. I have a matrix of character strings, which are time stamps, > time.m[1:5,1:5] [,1] [,2] [,3] [,4] [,5] [1,] "08:00:20.799" "08:00:20.799" "08:00:20.799" "08:00:20.799" "08:00:20.799" [2,]

Hi All, I am attempting to work with some data from loggers. I have read in a .csv exported from MS Access that already has my dates and times (in 24 clock format), (with StringsAsFactors=FALSE). > head(tdata) LogData date time 1 77.16 2008/04/24 02:00 2 61.78 2008/04/24 04:00 3 75.44 2008/04/24 06:00 4 89.43 2008/04/24

Hi all, I'm having a little bit of trouble with some date conversions and am hoping someone can help me out. Thanks in advance. OK, I have two sources of data that provide date info in a csv file differently. I've attached a small zipped file with two text files that illustrate both. (Is it ok to send attachments to this list? Not sure. It's very small.) I need to be able to