how to change a date format in R - r

I need help in R program to change date format from "May 29, 2015" to "05,29,2015".I tried this "housing$SaleDate<- as.Date(housing$SaleDate,"%Y%M%D")" but did not work. Thanks

After converting to Date class, we may need format i.e.
library(lubridate)
str1 <- "May 29, 2015"
format(mdy(str1), '%m,%d,%Y')
[1] "05,29,2015"
For the OP's as.Date, it would be
housing$SaleDate <- format(as.Date(housing$SaleDate, "%b %d, %Y"), "%m,%d,%Y")

Related

Convert date to specific format as Month Date, year

Is there way to convert the below code into Mar 10, 2020?
weekdays.Date(as.Date("2020-03-10", format="%Y-%m-%d"))
I think this should work:
format(as.Date("2020-03-10"), "%b %d, %Y")
# "Mar 10, 2020"

convert "2014-05" into date format as "May 2015" for display in ggplot in R

I have date in this character format "2017-03" and I want to convert it in "March 2017" for display in ggplot in R. But when I try to convert it using as.Date("2017-03","%Y-%m") it gives NA
You can consider using zoo::as.yearmon function as:
library(zoo)
#Sample data
v <- c("2014-05", "2017-03")
as.yearmon(v, "%Y-%m")
#[1] "May 2014" "Mar 2017"
#if you want the month name to be in full. Then you can format yearmon type as
format(as.yearmon(v, "%Y-%m"), "%B %Y")
#[1] "May 2014" "March 2017"
Parse dates back and forth can be done like this:
The one you mentioned is done by quoting MKR:
Use zoo package
library(zoo)
date <- "2017-03"
as.yearmon(date, "%Y-%m")
#[1] "Mar 2017"
format(as.yearmon(date, "%Y-%m"), "%B %Y")
#[1] "March 2017"
If you want to parse March 2017 or other similar formats back to 2017-03:
Use hms package because base R doesn't provide a nice built-in class for date
library(hms)
DATE <- "March 1 2017"
parse_date(DATE, "%B %d %Y")
#[1] "2017-03-01"
Or if you are parsing dates with foreign language:
foreign_date <- "1 janvier 2018"
parse_date(foreign_date, "%d %B %Y", locale = locale("fr"))
#[1] "2018-01-01"
By using the locale = locale("language") you can parse dates with foreign months names to standard dates. Use this to check the language:
date_names_langs()
-Format:
-Year: %Y(4 digits) %y(2 digits; 00-69->2000-2069, 70-99 -> 1970-1999)
-Month: %m (2 digits), %b (abbreviation: Jan), %B full name January
-Day: %d (2 digits)

Converting written to numeric dates in R

What's the most elegant way to convert these example dates to numeric dates:
dates <- c("April 1, 2017", "June 27, 2017", "September 24, 2017")
I would like this as a result:
"01-04-2017", "27-06-2017", "24-09-2017"
Using base
as.Date(dates, format = "%B %d, %Y")
[1] "2017-04-01" "2017-06-27" "2017-09-24"
and then formatted
format(as.Date(dates, format = "%B %d, %Y"), "%d-%m-%Y")
[1] "01-04-2017" "27-06-2017" "24-09-2017"
You could use mdy function of lubridate package to parse dates. Then use format to convert it to desired form.
library(lubridate)
format(mdy(dates), "%d-%m-%Y")
#[1] "01-04-2017" "27-06-2017" "24-09-2017"

How do I convert "January 30, 2015" to a date object in R?

I have a dataframe, and one of the columns are dates that are stored in the format "month_name day, year" (e.g. "December 25, 2016"). How do I convert these to date objects? Upon searching, I came across the following code:
df$date <- as.Date(df$date, format="%m/%d/%Y")
But upon viewing the data, the date column is NA.
You can try:
as.Date("December 25, 2016", format = '%B %d, %Y')
#[1] "2016-12-25"
You need to specify the format argument in as.Date based on how your dates look like. The full details of all the options are in ?strptime.
library(lubridate)
mdy("December 25, 2016")
#[1] "2016-12-25"
Or you can use the all inclusive anytime package which handles almost all the cases.
library(anytime)
anytime("December 25, 2016")
#[1] "2016-12-25 MYT"

Convert numeric data such as "715" into Date "July-2015" in R

I would like to friendly ask a question about converting numeric data into Date format.
I would like to convert the numeric data like:
time1<-c(715, 1212, 0416)
to
July-2015, Dec-2012, Apr-2016
I have tried these code but it is not working.
time2<-as.Date(as.character(time1), format="%m%y")
Does anyone have some ideas to solve this issue?
Part of the issue is that "July 2015", "December 2012", and "April 2016" are not dates since the specific day is missing. Another approach is to convert to zoo::yearmon. Here, the numeric input needs to be converted to a string with leading zero so that the month is from 01 to 12:
library(zoo)
ym <- as.yearmon(sprintf("%04d",time1),format="%m%y")
ym
##[1] "Jul 2015" "Dec 2012" "Apr 2016"
The result is of class yearmon, which can then be coerced to Date:
class(ym)
##[1] "yearmon"
d <- as.Date(ym)
d
##[1] "2015-07-01" "2012-12-01" "2016-04-01"
class(d)
##[1] "Date"
Try lubridate::parse_date_time():
library(lubridate)
time2 <- parse_date_time(time1, orders = "my")
format.Date(time2, "%b-%Y")
[1] "juil.-2015" "déc.-2012" "avril-2016" # my locale lang is French

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