I have tried a number of methods to no avail. I have data in terms of a date (YYYY-MM-DD) and am trying to get in terms of just the month and year, such as: MM-YYYY or YYYY-
Here's another solution using a package solely dedicated to working with dates and times in R:
library(tidyverse)
library(lubridate)
(df <- tibble(ID = 1:3, Date = c("2004-02-06" , "2006-03-14", "2007-07-16")))
#> # A tibble: 3 x 2
#> ID Date
#>
#> 1 1 2004-02-06
#> 2 2 2006-03-14
#> 3 3 2007-07-16
df %>%
mutate(
Date = ymd(Date),
Month_Yr = format_ISO8601(Date, precision = "ym")
)
#> # A tibble: 3 x 3
#> ID Date Month_Yr
#>
#> 1 1 2004-02-06 2004-02
#> 2 2 2006-03-14 2006-03
#> 3 3 2007-07-16 2007-07
Created on 2020-09-01 by the reprex package (v0.3.0)