Extracting year from a column that contains dates in m/d/yyyy format

Question

I have a dataset called verts imported from Excel with a column called Date that contains dates in this format: m/d/yyyy. I'm trying to extract the year from this column.

Here's what I'm currently trying:

verts$Date_converted <- strptime(verts$Date, format = "%m-%d-%y")   
verts$Year <- format(verts$Date_converted, "%y")

This produced two new columns in R, as you can see in the image, but both columns only contain NA.

Any ideas on what I'm doing wrong?

Answer 1

I recommend using package lubridate for dates - it makes everything so much easier.

• mdy() quickly parses a date that's written in the US format - regardless of delimiter type.
• year() extracts the year from an object in date format.

verts <- data.frame(Date = c("6/8/2004", "6/14/2004", "7/7/2006"))

verts <- verts |> 
  dplyr::mutate(Date_converted = lubridate::mdy(Date),
                year = lubridate::year(Date_converted))

verts
#>        Date Date_converted year
#> 1  6/8/2004     2004-06-08 2004
#> 2 6/14/2004     2004-06-14 2004
#> 3  7/7/2006     2006-07-07 2006

^{Created on 2022-04-22 by the reprex package (v2.0.1)}

PS please don't use screenshots for data - we can't import that into R. Read here to make it more likely for you to get help.