fm_crs_wkt: Handling CRS/WKT

In fmesher: Triangle Meshes and Related Geometry Tools

Handling CRS/WKT

Description

Get and set CRS object or WKT string properties.

Usage

fm_wkt_is_geocent(wkt)

fm_crs_is_geocent(crs)

fm_wkt_get_ellipsoid_radius(wkt)

fm_crs_get_ellipsoid_radius(crs)

fm_ellipsoid_radius(x)

## Default S3 method:
fm_ellipsoid_radius(x)

## S3 method for class 'character'
fm_ellipsoid_radius(x)

fm_wkt_set_ellipsoid_radius(wkt, radius)

fm_ellipsoid_radius(x) <- value

## S3 replacement method for class 'character'
fm_ellipsoid_radius(x) <- value

## S3 replacement method for class 'CRS'
fm_ellipsoid_radius(x) <- value

## S3 replacement method for class 'fm_CRS'
fm_ellipsoid_radius(x) <- value

## S3 replacement method for class 'crs'
fm_ellipsoid_radius(x) <- value

## S3 replacement method for class 'fm_crs'
fm_ellipsoid_radius(x) <- value

fm_crs_set_ellipsoid_radius(crs, radius)

fm_wkt_unit_params()

fm_wkt_get_lengthunit(wkt)

fm_wkt_set_lengthunit(wkt, unit, params = NULL)

fm_crs_get_lengthunit(crs)

fm_crs_set_lengthunit(crs, unit)

fm_length_unit(x)

## Default S3 method:
fm_length_unit(x)

## S3 method for class 'character'
fm_length_unit(x)

fm_length_unit(x) <- value

## S3 replacement method for class 'character'
fm_length_unit(x) <- value

## S3 replacement method for class 'CRS'
fm_length_unit(x) <- value

## S3 replacement method for class 'fm_CRS'
fm_length_unit(x) <- value

## S3 replacement method for class 'crs'
fm_length_unit(x) <- value

## S3 replacement method for class 'fm_crs'
fm_length_unit(x) <- value

fm_wkt(crs)

fm_proj4string(crs)

fm_wkt_tree_projection_type(wt)

fm_wkt_projection_type(wkt)

fm_crs_projection_type(crs)

fm_crs_bounds(crs, warn.unknown = FALSE)

## S3 replacement method for class 'inla.CRS'
fm_ellipsoid_radius(x) <- value

## S3 replacement method for class 'inla.CRS'
fm_length_unit(x) <- value

Arguments

wkt	A WKT2 character string
crs	An sf::crs, sp::CRS, fm_crs or inla.CRS object
x	crs object to extract value from or assign values in
radius	numeric; The new radius value
value	Value to assign
unit	character, name of a unit. Supported names are "metre", "kilometre", and the aliases "meter", "m", International metre", "kilometer", and "km", as defined by fm_wkt_unit_params or the params argument.
params	Length unit definitions, in the list format produced by fm_wkt_unit_params(), Default: NULL, which invokes fm_wkt_unit_params()
wt	A parsed wkt tree, see fm_wkt_as_wkt_tree()
warn.unknown	logical, default FALSE. Produce warning if the shape of the projection bounds is unknown.

Value

For fm_wkt_unit_params, a list of named unit definitions

For fm_wkt_get_lengthunit, a list of length units used in the wkt string, excluding the ellipsoid radius unit.

For fm_wkt_set_lengthunit, a WKT2 string with altered length units. Note that the length unit for the ellipsoid radius is unchanged.

For fm_crs_get_lengthunit, a list of length units used in the wkt string, excluding the ellipsoid radius unit.

For ⁠fm_length_unit<-⁠, a crs object with altered length units. Note that the length unit for the ellipsoid radius is unchanged.

Functions

• fm_wkt(): Returns a WKT2 string, for any input supported by fm_crs().

• fm_proj4string(): Returns a proj4 string, for any input supported by fm_crs().

• fm_wkt_tree_projection_type(): Returns "longlat", "lambert", "mollweide", "hammer", "tmerc", or NULL

• fm_wkt_projection_type(): See fm_wkt_tree_projection_type

• fm_crs_projection_type(): See fm_wkt_tree_projection_type

• fm_crs_bounds(): Returns bounds information for a projection, as a list with elements type ("rectangle" or "ellipse"), xlim, ylim, and polygon.

Author(s)

Finn Lindgren [e-mail]

See Also

fm_crs()

Examples

c1 <- fm_crs("globe")
fm_length_unit(c1)
fm_length_unit(c1) <- "m"
fm_length_unit(c1)

fmesher documentation built on Aug. 9, 2025, 1:10 a.m.