Circle

class compas.geometry.Circle[source]

Bases: Conic

A circle is a curve defined by a coordinate system and a radius.

The centre of the circle is at the origin of the coordinate system. The z-axis of the coordinate system defines the normal of the circle plane. The parameter domain is normalized with respect to the polar angle. A parameter value of t = 0 corresponds to the point on the circle at angle 0. A parameter value of t = 1 corresponds to the point on the circle at angle 2 * pi. Moving along the circle in the parameter direction corresponds to moving counter-clockwise around the origin of the local coordinate system.

Parameters:

radiusfloat: The radius of the circle.
framecompas.geometry.Frame, optional: The coordinate frame of the circle. The default value is None, in which case the world coordinate system is used.
namestr, optional: The name of the circle.

See also

compas.geometry.Ellipse, compas.geometry.Arc

Examples

Construct a circle in the world XY plane.

>>> from compas.geometry import Frame, Circle
>>> circle = Circle(radius=5, frame=Frame.worldXY())
>>> circle = Circle(radius=5)

Construct a circle such that the Z axis of its frame such that it aligns with a given line.

>>> from compas.geometry import Line, Frame, Plane, Circle
>>> line = Line([0, 0, 0], [1, 1, 1])
>>> plane = Plane(line.end, line.direction)
>>> circle = Circle.from_plane_and_radius(plane, 5)
>>> circle = Circle(radius=5, frame=Frame.from_plane(plane))

Visualise the line, circle, and frame of the circle with the COMPAS viewer.

>>> from compas_viewer import Viewer  
>>> viewer = Viewer()  
>>> viewer.scene.add(line)  
>>> viewer.scene.add(circle)  
>>> viewer.scene.add(circle.frame)  
>>> viewer.show()  

Attributes:

framecompas.geometry.Frame: The coordinate frame of the circle.
transformationTransformation, read-only: The transformation from the local coordinate system of the circle (frame) to the world coordinate system.
centercompas.geometry.Point: The center of the circle.
radiusfloat: The radius of the circle.
diameterfloat, read-only: The diameter of the circle.
areafloat, read-only: The area of the circle.
circumferencefloat, read-only: The circumference of the circle.
eccentricityfloat, read-only: The eccentricity of the circle is zero.
is_closedbool, read-only: True.
is_periodicbool, read-only: True.

Methods

`closest_point`	Compute the closest point on the circle to a given point.
`contains_point`	Verify that the circle contains a given point.
`from_plane_and_radius`	Construct a circle from a plane and a radius.
`from_point_and_radius`	Construct a circle from a point and a radius.
`from_points`	Construct a circle from a list of at least three points.
`from_three_points`	Construct a circle from three points.
`normal_at`	Construct a normal on the circle at a specific parameter.
`point_at`	Construct a point on the circle at a specific parameter.
`tangent_at`	Construct a tangent on the circle at a specific parameter.

Inherited Methods

`ToString`	Converts the instance to a string.
`aabb`	Compute the axis-aligned bounding box of the curve.
`compute_aabb`	Compute the axis-aligned bounding box of the geometry.
`compute_obb`	Compute the oriented bounding box of the geometry.
`copy`	Make an independent copy of the data object.
`curvature_at`	Compute the curvature vector of the curve at a parameter.
`divide_by_count`	Compute the curve parameters that divide the curve into a specific number of equal length segments.
`divide_by_length`	Compute the curve parameters that divide the curve into segments of specified length.
`fair`
`frame_at`	Compute the local frame of the curve at a parameter.
`from_json`	Construct an object of this type from a JSON file.
`from_jsonstring`	Construct an object of this type from a JSON string.
`from_obj`	Load a curve from an OBJ file.
`from_step`	Load a curve from a STP file.
`length`	Compute the length of the curve.
`offset`
`reverse`	Reverse the parametrisation of the curve.
`reversed`	Reverse a copy of the curve.
`rotate`	Rotate the geometry.
`rotated`	Returns a rotated copy of this geometry.
`scale`	Scale the geometry.
`scaled`	Returns a scaled copy of this geometry.
`sha256`	Compute a hash of the data for comparison during version control using the sha256 algorithm.
`smooth`
`split`
`to_json`	Convert an object to its native data representation and save it to a JSON file.
`to_jsonstring`	Convert an object to its native data representation and save it to a JSON string.
`to_obj`	Write the curve geometry to an OBJ file.
`to_points`	Convert the curve to a list of points.
`to_polygon`	Convert the curve to a polygon.
`to_polyline`	Convert the curve to a polyline.
`to_step`	Write the curve geometry to a STP file.
`transform`	Transform the local coordinate system of the curve.
`transformed`	Returns a transformed copy of this geometry.
`translate`	Translate the geometry.
`translated`	Returns a translated copy of this geometry.
`trim`
`validate_data`	Validate the data against the object's data schema.