You can use the strptime() function to convert a character to a timestamp in R. This function uses the following basic syntax:
strptime(character, format = “%Y-%m-%d %H:%M:%S”)
where:
- character: The name of the character to be converted
- format: The timestamp format to convert the character to
This tutorial provides several examples of how to use this syntax in practice.
Example 1: Convert Character to Year-Month-Day Format
The following code shows how to convert a character to a timestamp with a year-month-date format:
#create character variable char <- "2021-10-15" #display class of character variable class(char) [1] "character" #convert character to timestamp time <- strptime(char, "%Y-%m-%d") #display timestamp variable time [1] "2021-10-15 UTC" #display class of timestamp variable class(time) [1] "POSIXlt" "POSIXt"
Example 2: Convert Character to Hours-Minutes-Seconds Format
The following code shows how to convert a character to a timestamp with hours, minutes, and seconds included:
#create character variable char <- "2021-10-15 4:30:00" #convert character to timestamp time <- strptime(char, "%Y-%m-%d %H:%M:%S") #display timestamp variable time [1] "2021-10-15 04:30:00 UTC"
Example 3: Convert Character to Timestamp and Specify Time Zone
The following code shows how to convert a character to a timestamp and specify the time zone as Eastern Standard Time using the tz argument:
#create character variable char <- "2021-10-15" #convert character to timestamp with specific time zone time <- strptime(char, "%Y-%m-%d", tz="EST") #display timestamp variable time [1] "2021-10-15 EST"
Example 4: Convert a Data Frame Column to Timestamp
The following code shows how to convert a column in a data frame from a character to a timestamp:
#create data frame
df <- data.frame(date=c("2021-10-15", "2021-10-19", "2021-10-20"),
sales=c(4, 13, 19))
#display data frame
class(df$date)
[1] "character"
#convert date column to timestamp
df$date <- strptime(df$date, "%Y-%m-%d")
#display class of date column
class(df$date)
[1] "POSIXlt" "POSIXt"
You can find more R tutorials on this page.