Generate a tibble of epochs.

make_epochs(
  start_year = 1987,
  end_year = 2020,
  epoch_step = 5,
  epoch_overlap = TRUE
)

Arguments

start_year: Minimum year in epochs
end_year: Maximum year in epochs
epoch_step: Numeric. How many years in an epoch?
epoch_overlap: Logical. Should epochs overlap by one year? i.e. epoch_step = 10 with epoch_overlap = TRUE gives, say, 2000-2010 and 2010-2020 whereas epoch_overlap = FALSE gives 2000-2009 and 2010-2019.

Value

Tibble with columns

start: First year of epoch
end: Last year of epoch
years: List column containing the years for the epoch
epoch: Last two digits of first year and last year in epoch. e.g. 10-19.
data: List column of full path of raster files to summarise.

Examples

now <- as.numeric(format(Sys.Date(), "%Y"))
make_epochs(now - 30, now, 10)
#> # A tibble: 3 × 5
#>   start_year end_year years      epoch epoch_now
#>        <dbl>    <dbl> <list>     <ord> <lgl>    
#> 1       1996     2006 <int [11]> 96-06 FALSE    
#> 2       2006     2016 <int [11]> 06-16 FALSE    
#> 3       2016     2026 <int [11]> 16-26 TRUE     
make_epochs(now - 30, now, 10, F)
#> # A tibble: 4 × 5
#>   start_year end_year years      epoch epoch_now
#>        <dbl>    <dbl> <list>     <ord> <lgl>    
#> 1       1996     1996 <int [1]>  96-96 FALSE    
#> 2       1997     2006 <int [10]> 97-06 FALSE    
#> 3       2007     2016 <int [10]> 07-16 FALSE    
#> 4       2017     2026 <int [10]> 17-26 TRUE