5.2 Convert String to Date
20220523
The lubridate (Spinu, Grolemund, and Wickham 2023) package is the go to package for converting strings that represent a date into the date and time formats for computing with dates. A number of support functions are provided to perform the conversions quickly, including lubridate::ymd()
<- ymd("20220108") dt
Let’s have a look at the value:
dt
## [1] "2022-01-08"
Often we will want to do this in wrangling a dataset as part of a dplyr::mutate() operation:
"summary.csv" %>%
read_csv(show_col_types=FALSE) %>%
mutate(date=ymd(date)) %>%
...
The generic operation to convert a string to a date, where the string
might be in the format 20220204_121556
(that is year, month, day,
then hour, minute seconds) is lubridate::parse_date_time():
%>%
ds mutate(timestamp=parse_date_time(timestamp,
"Ymd_HMS",
tz="Australia/Canberra"))
Notice we’ve also included a time zone for the supplied timestamp with
the tz=
parameter.
References
Spinu, Vitalie, Garrett Grolemund, and Hadley Wickham. 2023. Lubridate: Make Dealing with Dates a Little Easier. https://CRAN.R-project.org/package=lubridate.
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