Geometries can be ill-defined for several reasons, e.g. circles with a radius of zero, segments that start and end at the same location, etc. See details for a list of conditions that are considered degenerate.

is_degenerate(x)

## Arguments

x A geometry vector

A logical vector

## Details

The following conditions are considered to produce degenerate geometries:

• A circle having a radius of zero

• An iso-rectangle with zero width or zero height

• An iso-cuboid with zero width, zero height, or zero depth

• A 2D line with the coefficients being zero

• A 3D line that is degenerated to a point

• A plane with the coefficients being zero

• A ray with the source and the second defining point being equal

• A segment with the source and target being equal

• A sphere with a radius of zero

• A tetrahedron with all vertices being co-planar

• A triangle with collinear vertices

## Examples

# A line without direction
l <- line(point(0, 5), vec(0, 0))
is_degenerate(l)
#>  TRUE
# A circle without radius
circ <- circle(point(3, -1), 0)
is_degenerate(circ)
#>  TRUE