I have a column in my dataframe as datetime (factor) with the values as "15-10-2017 16:41:00".
I wanted this data to be converted as "2017-10-15 16:41:00".
When i try to convert this, I'm getting the timezone also as output.
I tried using tz="", usetz=F but no use.
Any suggestions ?
Code:
as.POSIXlt("15-10-2017 16:41:00",format = "%d-%m-%Y %H:%M:%S")
[1] "2017-10-15 16:41:00 IST"
From the help page of as.POSIXlt:
"" is the current time zone
which is the default.
That's why it does not work. You could remove the timezone information this way, and it will not show while printing:
my_datetime <- as.POSIXlt("15-10-2017 16:41:00",format = "%d-%m-%Y %H:%M:%S")
my_datetime$zone <- NULL
my_datetime
but I don't understand why you would want to do that. You should convert to GMT if you don't want to worry about the timezone. Also lubridate package has a nice force_tz function if you have to force some specific timezones.
If you are ok storing the datetime as a character instead of as a POSIXlt, then you can use strftime():
my_datetime <- as.POSIXlt("15-10-2017 16:41:00",format = "%d-%m-%Y %H:%M:%S")
strftime(my_datetime)
I do it like this:
strip.tz <- function(dt) {
fmt <- "%Y-%m-%d %H:%M:%S"
strptime(strftime(dt, format = fmt, tz=""), format = fmt, tz="UTC")
}
and you would use it like this:
my_datetime <- as.POSIXct("15-10-2017 16:41:00",format = "%d-%m-%Y %H:%M:%S")
strip.tz(my_datetime)
Related
In my table I have a timestamp column in which i want to change the format. I already tried multiple things but it doesnt work. I also can not find examples to change the format in the whole column. First i converted the column to POSIXct then Ive tried to adjsut the format:
#timestamp as POSIXct and lane as numeric
Flows_ALM_2019 %>%
mutate(timestamp = as.POSIXct(timestamp),lane = as.numeric(lane)) -> Flows_ALM_2019
#remove seconds from time in timestamp column
df <- strftime(timestamp, format= "%Y-%m-%d %H:%m")
after trying:
df_2019_tsb$timestamp <- format(df_2019_tsb$timestamp,format= "%Y-%m-%d %H:%m")
This is what I had:
and now it changed to:
What am i doing wrong?
You can use format :
Flows_ALM_2019$timestamp <- format(Flows_ALM_2019$timestamp, "%Y-%m-%d %H:%m")
Or with strftime.
Flows_ALM_2019$timestamp <- strftime(Flows_ALM_2019$timestamp, "%Y-%m-%d %H:%m")
This is assuming that timestamp column is of class POSIXct in your data.
My date value is in this format
02:27:16 05-Mar-2019, Tue stored in Assigned date column
Am converting
srdetails1$Assigned On GMT<-as.POSIXct(srdetails1$Assigned On GMT, tz="", format = "%H:%M:%S %m/%d/%Y")
srdetails$Assigned On GMT
the value get converted as
43497.067407407405
Instead of showing a date and any function i use on this column for
e.g :-
day(ymd_hms() etc gives me "NA"
How do i resolve this - Any help appreciated
When i trim the date with only m/d/y (without time) it works properly
Your format mask does not match the timestamp which you are trying to use with as.POSIXct. Consider the following version:
x <- "02:27:16 05-Mar-2019"
as.POSIXct(x, tz="", format = "%H:%M:%S %d-%b-%Y")
[1] "2019-03-05 02:27:16 CET"
We can use anytime
library(anytime)
addFormats("%H:%M:%S %d-%b-%Y")
anytime(x)
#[1] "2019-03-05 02:27:16 EST"
data
x <- "02:27:16 05-Mar-2019"
I have a column of dates which were read in as character values (yes, they are supposed to be the same):
str(df$date)
$ date : chr "30/08/2017" "30/08/2017" "30/08/2017" "30/08/2017"
I then convert the values to Date format:
str(df$date)
$ date : Date, format: "2017-08-30" "2017-08-30" "2017-08-30"
The problem is that no matter which method I choose to use, the resulting dates are always in YYYY/MM/DD format, which is not what I want; they should be in DD/MM/YYYY format.
I try:
df$date <- as.Date(df$date, format = "%d/%m/%Y")
df$date <- strptime(df$date, format = "%d/%m/%Y")
df$date <- as.POSIXct(df$date, format = "%d/%m/%Y")
and they all produce the same format.
I have read numerous similar Stack Overflow posts as well as some guides and have tried things like getting and setting my system locale (United Kingdom) and all is correct in that respect.
Where am I going wrong?
I try:
df$date <- as.Date(df$date, format = "%d/%m/%Y")
df$date <- strptime(df$date, format = "%d/%m/%Y")
df$date <- as.POSIXct(df$date, format = "%d/%m/%Y")
and they all produce the same format.
R has two very similarly named functions: strptime, which converts from character strings to Date data, and strftime, which converts Dates to formatted strings. To make matters worse, the documentation for these two functions is combined, so it can be very hard to keep their uses straight. You want strftime, in this case.
You can also use format:
date = c("30/08/2017", "30/08/2017", "30/08/2017", "30/08/2017")
date <- as.Date(date, format = "%d/%m/%Y")
# > date
# [1] "2017-08-30" "2017-08-30" "2017-08-30" "2017-08-30"
date = format(date, "%m/%d/%Y")
# > date
# [1] "08/30/2017" "08/30/2017" "08/30/2017" "08/30/2017"
Turns into character class:
# > class(date)
# [1] "character"
This will help you:
$variable = '2018/09/18';
$date = str_replace('/', '/', $variable);
echo date('d/m/Y', strtotime($date));
Please check and let me know if you need any more help.
How one goes about to reformat date to CCYYMMDD HH:MM:SS TZ ? (the TZ is optional)
Here is related post but I would need the solution within R.
Here are my dates, which I would need to reformat.
library(lubridate)
startdate <- as.Date("2015-01-01")
week.dates <- seq(startdate, by="1 week", length.out=12)
dat.week <- week.dates[wday(week.dates) != 1 & wday(week.dates) != 7]
biz.week <- format(as.POSIXct(as.Date(dat.week)), tz="America/Los_Angeles",usetz=TRUE)
EDIT: Specifically, needed format is: 'YYYYMMDD{SPACE}hh:mm:ss[{SPACE}TMZ]'
Just try:
strftime(dat.week,format="%Y%m%d %H:%M %Z")
You can also use format or as.character instead of strftime.
I think you also requested the seconds, so here's a minor modification:
strftime(dat.week,format="%C%y%m%d %H:%M:%S %Z")
This question might be simple for some of you but bear with me since I'm a beginner in R.
I have a dataframe that has a factor column (called time) containing DateTime data as the following:
time
01/01/2011 00:10
02/01/2011 03:00
03/01/2011 05:00
04/01/2011 10:03
I want to convert this column into DateTime column in R. I searched and tried some functions but it gives me 'NA' results. The following functions are those I tried:
> dataframe1$datetime <- as.POSIXlt(as.character(dataframe1$time), format="%d/%m/%Y %H:%M")
> dataframe1$datetime <- as.POSIXlt(strptime(dataframe1$time), format="%d/%m/%Y %H:%M")
> dataframe1$datetime <- as.POSIXlt(dataframe1$time, format="%d/%m/%Y %H:%M")
> dataframe1$datetime <- as.chron(dataframe1$time, "%d/%m/%Y %H:%M")
I don't know what else to try. I want ideally to add three columns namely datetime, date, and time.
Try:
dataframe1$datetime <- strptime(x = as.character(dataframe1$datetime),
format = "%d/%m/%Y %H:%M")
Probably the easiest thing to do is use the lubridate packages which has a large number of functions for date manipulation. The following will convert your time into a POSIXct object:
library(lubridate)
mdy_hm( as.character(dataframe1$time) )
See ?mdy to see the variety of date parsing functions.
For a slightly more verbose version that does not rely on lubridate
strptime(x = as.character( dataframe1$datetime ), format = "%d/%m/%Y %H:%M")