Class: QgsEllipse

class qgis.core.QgsEllipse

Bases: sip.wrapper

Constructor for QgsEllipse.

QgsEllipse(center: QgsPoint, semiMajorAxis: float, semiMinorAxis: float, azimuth: float = 90) Constructs an ellipse by defining all the members.

Parameters:
  • center – The center of the ellipse.
  • semiMajorAxis – Semi-major axis of the ellipse.
  • semiMinorAxis – Semi-minor axis of the ellipse.
  • azimuth – Angle in degrees started from the North to the first quadrant.

QgsEllipse(QgsEllipse)

Ellipse geometry type.

An ellipse is defined by a center point with a semi-major axis, a semi-minor axis and an azimuth. The azimuth is the north angle to the first quadrant (always oriented on the semi-major axis), in degrees. By default, the semi-major axis is oriented to the east (90 degrees). The semi-minor axis is always smaller than the semi-major axis. If it is set larger, it will be swapped and the azimuth will increase by 90 degrees.

New in version 3.0: Enums

Methods

area The area of the ellipse.
azimuth Returns the azimuth.
boundingBox Returns the minimal bounding box for the ellipse.
center Returns the center point.
eccentricity The eccentricity of the ellipse.
foci Two foci of the ellipse.
focusDistance The distance between the center and each foci.
fromCenter2Points Constructs an ellipse by a central point and two other points.
fromCenterPoint Constructs an ellipse by a center point and a another point.
fromExtent Constructs an ellipse by an extent (aka bounding box / QgsRectangle).
fromFoci Constructs an ellipse by foci (pt1 and pt2) and a point pt3.
isEmpty An ellipse is empty if axes are equal to 0
orientedBoundingBox Returns the oriented minimal bounding box for the ellipse.
perimeter The circumference of the ellipse using first approximation of Ramanujan.
points Returns a list of points with segmentation from segments.
quadrant The four quadrants of the ellipse.
semiMajorAxis Returns the semi-major axis.
semiMinorAxis Returns the semi-minor axis.
setAzimuth Sets the azimuth (orientation).
setCenter Sets the center point.
setSemiMajorAxis Sets the semi-major axis.
setSemiMinorAxis Sets the semi-minor axis.
toLineString Returns a segmented linestring.
toPolygon Returns a segmented polygon.
toString returns a string representation of the ellipse.

Signals

Attributes

area(self) → float

The area of the ellipse.

azimuth(self) → float

Returns the azimuth.

See also

setAzimuth()

boundingBox(self) → QgsRectangle

Returns the minimal bounding box for the ellipse.

center(self) → QgsPoint

Returns the center point.

See also

setCenter()

See also

rcenter()

eccentricity(self) → float

The eccentricity of the ellipse. nan is returned if the ellipse is empty.

foci(self) → List[QgsPoint]

Two foci of the ellipse. The axes are oriented by the azimuth and are on the semi-major axis.

See also

fromFoci()

See also

focusDistance()

Returns:the two foci.
focusDistance(self) → float

The distance between the center and each foci.

See also

fromFoci()

See also

foci()

Returns:The distance between the center and each foci.
fromCenter2Points(ptc: QgsPoint, pt1: QgsPoint, pt2: QgsPoint) → QgsEllipse

Constructs an ellipse by a central point and two other points. The center point keeps m value from ptc. Z dimension is also supported and is retrieved from the first 3D point amongst ptc, pt1 and pt2. Axes are calculated from the 2D distance between ptc and pt1 and pt2. The azimuth is the angle between ptc and pt1.

Parameters:
  • ptc – Center point.
  • pt1 – First point.
  • pt2 – Second point.
fromCenterPoint(ptc: QgsPoint, pt1: QgsPoint) → QgsEllipse

Constructs an ellipse by a center point and a another point. The center point keeps m value from ptc. Z dimension is also supported and is retrieved from the first 3D point amongst ptc and pt1. Axes are calculated from the 2D distance between ptc and pt1. The azimuth always takes the default value.

Parameters:
  • ptc – Center point.
  • pt1 – First point.
fromExtent(pt1: QgsPoint, pt2: QgsPoint) → QgsEllipse

Constructs an ellipse by an extent (aka bounding box / QgsRectangle). The center point can have m value which is the result from the midpoint operation between pt1 and pt2. Z dimension is also supported and is retrieved from the first 3D point amongst pt1 and pt2. Axes are calculated from the 2D distance between pt1 and pt2. The azimuth always takes the default value.

Parameters:
  • pt1 – First corner.
  • pt2 – Second corner.
fromFoci(pt1: QgsPoint, pt2: QgsPoint, pt3: QgsPoint) → QgsEllipse

Constructs an ellipse by foci (pt1 and pt2) and a point pt3. The center point can have m value which is the result from the midpoint operation between pt1 and pt2. Z dimension is also supported and is retrieved from the first 3D point amongst pt1 and pt2. Axes are calculated from the 2D distance with the third point pt3. The azimuth is the angle between pt1 and pt2.

Parameters:
  • pt1 – First focus.
  • pt2 – Second focus.
  • pt3 – A point to calculate the axes.
isEmpty(self) → bool

An ellipse is empty if axes are equal to 0

orientedBoundingBox(self) → QgsPolygon

Returns the oriented minimal bounding box for the ellipse.

perimeter(self) → float

The circumference of the ellipse using first approximation of Ramanujan.

points(self, segments: int = 36) → object

Returns a list of points with segmentation from segments.

Parameters:segments – Number of segments used to segment geometry.
quadrant(self) → List[QgsPoint]

The four quadrants of the ellipse. They are oriented and started always from semi-major axis.

Returns:quadrants defined by four points.
semiMajorAxis(self) → float

Returns the semi-major axis.

semiMinorAxis(self) → float

Returns the semi-minor axis.

setAzimuth(self, azimuth: float)

Sets the azimuth (orientation).

See also

azimuth()

setCenter(self, center: QgsPoint)

Sets the center point.

See also

center()

See also

rcenter()

setSemiMajorAxis(self, semiMajorAxis: float)

Sets the semi-major axis.

See also

semiMajorAxis()

setSemiMinorAxis(self, semiMinorAxis: float)

Sets the semi-minor axis.

See also

semiMinorAxis()

toLineString(self, segments: int = 36) → QgsLineString

Returns a segmented linestring.

Parameters:segments – Number of segments used to segment geometry.
toPolygon(self, segments: int = 36) → QgsPolygon

Returns a segmented polygon.

Parameters:segments – Number of segments used to segment geometry.
toString(self, pointPrecision: int = 17, axisPrecision: int = 17, azimuthPrecision: int = 2) → str

returns a string representation of the ellipse. Members will be truncated to the specified precision.