Get the projection of a grid reference

This function returns the grid reference's projection, either as OSGB or OSNI.

projection(x)

# S3 method for gridref
projection(grid_reference)

Arguments

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

Value

The projection of the grid reference in British National Grid (OSGB) or Irish National Grid (OSNI).

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(), monad(), northing(), pentad(), precision(), 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 projection column
suppressPackageStartupMessages({
  suppressWarnings({
    library(dplyr)
  })
})

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