Get the 1km grid reference

This function returns the 1km grid reference for a higher precision grid reference.

monad(x)

# S3 method for gridref
monad(grid_reference)

Arguments

grid_reference	A Great British or Irish grid reference character string with class gridref.

Value

The grid reference at 2km resolution.

Details

It can check either British or Irish grid references up to 10 figure (1m precision), including tetrads (2000m precision).

REST API

A REST API endpoint is available once a Plumber router has been created and can be requested by adding _api to the end of the function.

The API returns "" instead of NULL so that it may be used with the dplyr::mutate function. Wrap the API call with dplyr::na_if to convert "" to NA.

suppressPackageStartupMessages({
  library(store)
  suppressWarnings({
    library(plumber)
  })
})
pr("../R/gridref_api.R") %>%
  pr_run(port = 8000)

See also

Other grid reference functions: easting(), gridsquare_geometry(), hectad(), hectare(), northing(), pentad(), precision(), projection(), tetrad()

Examples

 suppressPackageStartupMessages({
   library(store)
   suppressWarnings({
     library(dplyr)
     library(janitor)
   })
 })

 grid_references <- nbn_demonstration_dataset %>%
   clean_names() %>%
   slice_tail(n = 15) %>%
   select(grid_reference) %>%
   mutate(grid_reference = as_gridref(grid_reference))


# add one_km column
suppressPackageStartupMessages({
  suppressWarnings({
    library(dplyr)
  })
})

grid_references %>%
  rowwise() %>%
  mutate(one_km = monad(grid_reference))
#> # A tibble: 15 x 2
#> # Rowwise: 
#>    grid_reference one_km
#>    <gridref>      <chr> 
#>  1 TL2384         TL2384
#>  2 TL232839       TL2383
#>  3 TL2385         TL2385
#>  4 TL231840       TL2384
#>  5 TL232839       TL2383
#>  6 TL23248346     TL2383
#>  7 TL23568493     TL2384
#>  8 TL23448505     TL2385
#>  9 TL23128324     TL2383
#> 10 TL234850       TL2385
#> 11 TL234846       TL2384
#> 12 TL232839       TL2383
#> 13 TL231841       TL2384
#> 14 TL226846       TL2284
#> 15 TL2384         TL2384