I am not too great with manipulating dates in R, and am currently stuck on trying to convert a date that has an ambiguous format into a Date object. My dates are in the format 20150122, for example. When I use as.Date, I get an error like:
d7$Search.Date <- as.Date(d7$Search.Date, "%y%m%d")
Error in charToDate(x) :
character string is not in a standard unambiguous format
How can I convert these currently? Thank you.
We need to use %Y as the year part is 4 digits, %y is used when it is 2 digit.
as.Date(d7$Search.Date, "%Y%m%d")
For example
as.Date("20150122", "%Y%m%d")
#[1] "2015-01-22"
For more info regarding the format, check ?strptime
Related
I am currently working with a data set with a million rows where all of the dates are not in the standard unambiguous format that R requires. I have worked on trying to reformat the date-time to the standard unambiguous format but have had zero luck. I have tried using functions such as format, as.POSIXlt and as.POSIXct but with no luck.
The format is currently "%m/%d/%Y %H:%M:%OS" and I need to reformat it as "%Y/%m/%d %H:%M:%OS".
Any help is appreicated.
Using the lubridate package from tidyverse, you can readily convert to your desired format.
library(lubridate)
oldformat <- as.character("10/13/2022 01:12:33")
newformat <- mdy_hms(oldformat)
I have a list of data that has date information in the format:
11-Feb-08, 13-Feb-08, 2-Mar-08 etc. How can I change all the entries in this column to be in dd/mm/yy format. I have tried as.Date and as.POSIXct but it converts it to NAs. sos pls help.
You are getting NAs for the date values because of the formatting issue. Provide appropriate date format in format argument of as.POSIXct or as.Date function.
As per the date example(11-Feb-08), the appropriate format would be :
format = '%d-%b-%y'.
Do look at the documentation using ?strptime for format related query.It is well documented for each kind of date format.
You can try below Code using lubridate
library(lubridate)
c<-data.frame("Date" = c("11-Feb-08","13-Feb-08", "2-Mar-08"))
c$Date<-dmy(c$Date, tz = "Asia/Kolkata")
str(c$Date)
You will get below result:
POSIXct[1:3], format: "2008-02-11" "2008-02-13" "2008-03-02"
I have a data set that has a column for dates (emp2$hiredate) which is in char format. While converting it to Date, I'm getting the following error :
> date1 <- emp2$hiredate[2]
> str(date1)
chr "20FEB1981"
> as.POSIXct(date1)
Error in as.POSIXlt.character(x, tz, ...) :
character string is not in a standard unambiguous format
How do I solve this problem?
R doesn't automatically know the format of the date in the string. You need to use the format argument to tell it how to process the string.
You can use as.Date to create a date
as.Date("20FEB1981", "%d%b%Y")
# [1] "1981-02-20"
Or use as.POSIXct with the format option to create a date-time
as.POSIXct("20FEB1981", format = "%d%b%Y")
# [1] "1981-02-20 PST"
%d means the day of the month in decimal form
%b means that the month is not in numeric form, but rather an abbreviated name
%Y (capitalized) means the year is in century form (all four numbers)
i have date in this format:
1397758632
and i need to convert them into dates in this format %Y-%m-%d.
how can i do this? my timezone is GTM.
Using as.POSIXct() function in this way:
as.POSIXct(x="1397758632",origin="1960-01-01", tz="GMT")
i have this error
Error in as.POSIXlt.character(x, tz, ...) : character string is not in a standard unambiguous format
how can i obtain a readable data?
A couple of things, if you have defined a variable x = "1397758632" you don't have to declare it again, just use x. eg// as.POSIXct(x,origin="1970-01-01", tz="GMT")
2nd, x="1397758632" is actually a char variable, try str(x) you would want to declare it as numeric, x=1397758632 and you should be all good.
Lastly, add as.Date() if you just want the date and not the whole time stamp.
So something like:
x=1397758632
as.POSIXct(x,origin="1970-01-01", tz="GMT")
as.Date(as.POSIXct(x,origin="1970-01-01", tz="GMT")) # for just the date
My data contains a variable which recorded the date like "Wednesday 01/01/86". I want to drop the days like "Wednesday" and convert "01/01/86" into the format "1986-01-01".
I tried as.Date(myData$DATE) but I got an error message: character string is not in a standard unambiguous format. I assume this is due to the character Wednesday?
You have to tell as.Date what format your input is in:
as.Date("Wednesday 01/01/86", format="%A %m/%d/%y")
# "1986-01-01"
See docs for strptime for more details.