CODEWITHSUNDEEP
rdataframematrix
Alexander Glenmore
Alexander Glenmore

Reputation: 36

How can I change a series of dates into one date R?

I have a data frame of polls, one column of which is titled Date.s.administered, and is formatted as a string containing the dates for which the poll was administered. For example, "January 16-20, 2019", or "December 1-11, 2018". The entire column looks like this:

[1] "November 3–5, 2018"    "November 1–2, 2018"   
[3] "October 28–30, 2018"   "October 22–28, 2018"  
[5] "October 15–28, 2018"   "October 15–28, 2018"  
[7] "October 25–26, 2018"   "October 18–21, 2018"  
[9] "October 15–21, 2018"   "October 12–18, 2018"  
[11] "October 10–14, 2018"   "October 9–13, 2018"   
[13] "October 9–13, 2018"    "October 8–13, 2018"   
[15] "October 8–11, 2018"    "October 3–9, 2018"

How would I manipulate this column so that it displays only the last date of the series (for example, "March 1-4, 2018" becomes "March 4, 2018")?

Upvotes: 0

Views: 50

Answers (3)

tmfmnk
tmfmnk

Reputation: 40151

An approach using tidyverse could be:

date %>%
 separate(date, c("date1", "date2"), sep = "–") %>%
 mutate(date = paste(sub("[^[:alpha:]]+", "", date1), date2, sep = " ")) %>%
 select(date)

              date
1 November 2, 2018
2 October 28, 2018
3 October 28, 2018

First, it is separating the "date" column into "date1" and date2" based on "–". Then, it is keeping only letters from "date1" and combining it with "date2" into the desired "date" column.

Sample data:

date <- data.frame(date = c("November 1–2, 2018",
          "October 22–28, 2018",
          "October 15–28, 2018"))

Upvotes: 0

D.sen
D.sen

Reputation: 922

You could use the lubridate package in combination with regex to extract a string pattern then convert to a standard date field.

suppressPackageStartupMessages(library(lubridate))

x <- "March 1-4, 2018"

mdy(gsub("(^.+)(\\s\\d-)(\\d)(,\\s)(\\d{4}$)", '\\1 \\3 \\5', x))
#> [1] "2018-03-04"

Upvotes: 0

arg0naut91
arg0naut91

Reputation: 14764

You could do:

gsub("\\d+–", "", df$Date.s.administered)

Example data:

df <- data.frame(Date.s.administered = c("November 3–5, 2018", "November 1–2, 2018"))

Output:

[1] "November 5, 2018" "November 2, 2018"

Upvotes: 2

Related Questions