Access the exact values that defines the geometries

This function gives access to the underlying values defining the geometries in a vector. As such they return the same information as calling as.matrix() on a geometry vector except the return value is kept as an exact numeric and that you can extract from single elements if the cardinality of the geometry exceeds 1.

Usage

def(x, ...)

# S3 method for euclid_geometry
def(x, name, which = NULL, ...)

# S3 method for euclid_affine_transformation
def(x, i, j, ...)

def(x, ...) <- value

# S3 method for euclid_geometry
def(x, name, which = NULL, ...) <- value

# S3 method for euclid_affine_transformation
def(x, i, j, ...) <- value

definition_names(x, ...)

Arguments

x

A geometry vector

...

parameters to pass on

name

Either a name or the index of the definition to extract, as matched to definition_names(x)

which

An integer vector giving the vertex from which the definition should be extracted, or NULL to extract all to extract all.

i, j

The row and column of the cell in the transformation to fetch.

value

An exact_numeric vector or an object convertible to one

Value

An exact_numeric vector

See also

Other Geometry methods: euclid_geometry, subgeometries

Examples

# Get squared radius of circle
circ <- circle(point(4, 7), 25)
def(circ, "r2")
#> <exact numerics [1]>
#> [1] 25

# Set r2 to 10
def(circ, "r2") <- 10
circ
#> <2D circles [1]>
#> [1] <x:4, y:7, r2:10>

# Get all the x values from the source of segments
s <- segment(point(sample(10, 4), sample(10, 4)),
             point(sample(10, 4), sample(10, 4)))
def(s, "x", 1L)
#> <exact numerics [4]>
#> [1] 7 6 2 4

# Get y for all subelements
def(s, "y")
#> <exact numerics [8]>
#> [1] 5 9 9 7 7 6 6 2

# Extract cell values from transformation matrices
m <- affine_rotate(c(pi/2, pi/3))
def(m, 1, 2)
#> <exact numerics [2]>
#> [1] -1.0000000 -0.8660254