osbng (version 0.2.0)

bng_to_xy: Convert BNG References

Description

Create British National Grid references from coordinates at a specific resolution or convert grid reference objects to coordinates at a grid position.

Usage

bng_to_xy(
  bng_ref,
  position = c("lower-left", "upper-left", "upper-right", "lower-right", "centre"),
  ...
)
xy_to_bng(...)
# S3 method for numeric
xy_to_bng(easting, northing, resolution, ...)
# S3 method for matrix
xy_to_bng(x, resolution, ...)
# S3 method for data.frame
xy_to_bng(df, cols = c("eastings", "northings"), resolution, ...)

Value

• xy_to_bng: vector of BNGReference objects

• bng_to_xy: two-column matrix of eastings and northings

Arguments

bng_ref

vector of type BNGReference objects

position

character indicating which point location of the BNG grid square is returned. Default is the lower-left corner.

...

additional parameters, not currently used

easting

numeric vector of coordinates

northing

numeric vector of coordinates

resolution

target BNG grid resolution. Can be specified as a numeric or character vector

x

two column matrix of eastings and northings

df

data.frame with columns of coordinates to convert

cols

column names or indices within df holding coordinates

Details

Coordinates must be in British National Grid projection (EPSG:27700) using eastings and northings in meters. These functions do not support coordinate transformations.

Examples

bng_to_xy(as_bng_reference("SU"), "lower-left")

bng_to_xy(as_bng_reference("SU 3 1"), "lower-left")

bng_to_xy(as_bng_reference("SU 3 1 NE"), "centre")

bng_to_xy(as_bng_reference("SU 37289 15541"), "centre")

xy_to_bng(437289, 115541, "100km")

xy_to_bng(437289, 115541, "10km")

xy_to_bng(437289, 115541, "5km")

xy_to_bng(437289, 115541, 1)