gridRef: Manipulate OSGB or OSNI grid reference string

In gcfrench/store: Store commonly used functions and lookups

Manipulate OSGB or OSNI grid reference string

Description

Extracts grid reference strings at various precisions from the supplied grid reference string when possible. For example supplying a 1km square reference TL2998, will return the 10km square TL29 but not a 100m square grid reference.

Usage

gridRef(x)

Arguments

grid_reference	A Great British or Irish grid reference character string with class gridref
format	The required grid reference format, either sq10km, sq5km, tetrad, sq1km, sq100m or sq10m.

Details

Tetrads are 2x2km squares and are often used for mapping distributions at the scale of a county or similar sized local area. They are labelled using the 10km square followed by a single, upper-case letter. Since there are 25 tetrads in a 10km square, the letter "O" is not used to avoid confusion with zero. This is named the DINTY system after the letters in the second row of this table.

Pentads are 5x5km squares used for mapping at a regional scale. They are labelled using the name of the 10km square followed by two upper-case letters.

Value

The grid reference string formatted as requested.

Author(s)

Stuart Ball.

See Also

Function taken from archived rnbn package.

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