tetrad: Get the 2km grid reference

In gcfrench/store: Store commonly used functions and lookups

Get the 2km grid reference

Description

This function returns the 2km grid reference for a higher precision grid reference.

Usage

tetrad(x)

## S3 method for class 'gridref'
tetrad(grid_reference)

Arguments

grid_reference

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

Details

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

Value

The grid reference at 2km resolution.

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({
  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(), projection(), ten_metre()

Examples

 suppressPackageStartupMessages({
   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 two_km column
suppressPackageStartupMessages({
  suppressWarnings({
    library(dplyr)
  })
})

grid_references %>%
  rowwise() %>%
  mutate(two_km = tetrad(grid_reference))

gcfrench/store documentation built on Jan. 30, 2025, 2:59 p.m.