This is a utility function that is useful when plotting countries that have interrupted periods.
count_sequence_breaks(seq, seq_step = 1)A numeric sequence
The expected difference between steps in sequence
A numeric vector with the sequence groups
library(dplyr)
count_sequence_breaks(c(1900:1910, 1920:1930))
#> [1] 1 1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 2 2
# This is how I typically use it
polityIV %>%
group_by(polityIV_country, polityIV_ccode) %>%
mutate(groups = count_sequence_breaks(year)) %>%
filter(any(groups > 1))
#> # A tibble: 689 × 41
#> # Groups: polityIV_country, polityIV_ccode [7]
#> cyear polityIV_ccode scode polityIV_country year flag fragment democ autoc
#> <dbl> <dbl> <chr> <chr> <dbl> <dbl> <dbl> <dbl> <dbl>
#> 1 2.55e6 255 GMY Germany 1868 0 NA -88 -88
#> 2 2.55e6 255 GMY Germany 1869 0 NA -88 -88
#> 3 2.55e6 255 GMY Germany 1870 0 NA -88 -88
#> 4 2.55e6 255 GMY Germany 1871 0 NA 0 4
#> 5 2.55e6 255 GMY Germany 1872 0 NA 0 4
#> 6 2.55e6 255 GMY Germany 1873 0 NA 0 4
#> 7 2.55e6 255 GMY Germany 1874 0 NA 0 4
#> 8 2.55e6 255 GMY Germany 1875 0 NA 0 4
#> 9 2.55e6 255 GMY Germany 1876 0 NA 0 4
#> 10 2.55e6 255 GMY Germany 1877 0 NA 0 4
#> # ℹ 679 more rows
#> # ℹ 32 more variables: polity <dbl>, polity2 <dbl>, durable <dbl>, xrreg <dbl>,
#> # xrcomp <dbl>, xropen <dbl>, xconst <dbl>, parreg <dbl>, parcomp <dbl>,
#> # exrec <dbl>, exconst <dbl>, polcomp <dbl>, prior <dbl>, emonth <dbl>,
#> # eday <dbl>, eyear <dbl>, eprec <dbl>, interim <dbl>, bmonth <dbl>,
#> # bday <dbl>, byear <dbl>, bprec <dbl>, post <dbl>, change <dbl>, d4 <dbl>,
#> # sf <dbl>, regtrans <dbl>, extended_country_name <chr>, GWn <dbl>, …