precision: Get the precision of a grid reference

In gcfrench/store: Store commonly used functions and lookups

Get the precision of a grid reference

Description

This function returns the grid reference's precision in metres.

Usage

precision(x)

## S3 method for class 'gridref'
precision(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 precision of the grid reference in metres.

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

The function calls the gridCoords function in the archived rnbn package.

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

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

grid_references %>%
  rowwise() %>%
  mutate(precision = precision(grid_reference))

gcfrench/store documentation built on May 17, 2024, 5:52 p.m.