Friction period: lookups in days/weeks (1-year vs 5-year average)

tatooheene team

2025-12-15

What this vignette covers

The function is . Column names reflect the CBS table embedded in df_fp.

The underlying data

df_fp %>%
  select(Year,
         `Friction period in days`,
         `Friction period days average over 5 years`,
         `Friction period in weeks`,
         `Friction period weeks average over 5 years`) %>%
  head()
#> # A tibble: 6 × 5
#>    Year `Friction period in days` Friction period days …¹ Friction period in w…²
#>   <dbl>                     <dbl>                   <dbl>                  <dbl>
#> 1  1997                      NA                      NA                     NA  
#> 2  1998                      87.6                    NA                     12.5
#> 3  1999                      97.5                    NA                     13.9
#> 4  2000                     103.                     NA                     14.7
#> 5  2001                     101.                     NA                     14.5
#> 6  2002                      98.3                    97.5                   14.0
#> # ℹ abbreviated names: ¹​`Friction period days average over 5 years`,
#> #   ²​`Friction period in weeks`
#> # ℹ 1 more variable: `Friction period weeks average over 5 years` <dbl>

Quick starts

1) Default: all years, weeks, 5‑year average

tatooheene::friction_period()
#> # A tibble: 27 × 2
#>     Year `Friction period weeks average over 5 years`
#>    <dbl>                                        <dbl>
#>  1  1997                                         NA  
#>  2  1998                                         NA  
#>  3  1999                                         NA  
#>  4  2000                                         NA  
#>  5  2001                                         NA  
#>  6  2002                                         13.9
#>  7  2003                                         13.9
#>  8  2004                                         13.7
#>  9  2005                                         13.5
#> 10  2006                                         13.6
#> # ℹ 17 more rows

2) Specific year, weeks, 5‑year average → single value

tatooheene::friction_period(year = 2019, units = "weeks", avg = "5yr", output = "value")
#> [1] 14.26372

3) Days, 1‑year values for a range of years

tatooheene::friction_period(year = 2018:2020, units = "days", avg = "1yr")
#> # A tibble: 3 × 2
#>    Year `Friction period in days`
#>   <dbl>                     <dbl>
#> 1  2018                      107.
#> 2  2019                      111.
#> 3  2020                      102.

4) Multiple selections return multiple columns

tatooheene::friction_period(
  year  = 2015:2019,
  units = c("days", "weeks"),
  avg   = "1yr"       # try c("1yr","5yr") to get four columns
)
#> # A tibble: 5 × 3
#>    Year `Friction period in days` `Friction period in weeks`
#>   <dbl>                     <dbl>                      <dbl>
#> 1  2015                      87.2                       12.5
#> 2  2016                      92.2                       13.2
#> 3  2017                     101.                        14.5
#> 4  2018                     107.                        15.3
#> 5  2019                     111.                        15.9

Error messages you might see