Class: QgsCircle¶
-
class
qgis.core.
QgsCircle
¶ Bases:
qgis._core.QgsEllipse
QgsCircle(center: QgsPoint, radius: float, azimuth: float = 0) Constructs a circle by defining all the members.
- Parameters
center – The center of the circle.
radius – The radius of the circle.
azimuth – Angle in degrees started from the North to the first quadrant.
QgsCircle(QgsCircle)
Circle geometry type.
A circle is defined by a center point with a radius and an azimuth. The azimuth is the north angle to the semi-major axis, in degrees. By default, the semi-major axis is oriented to the north (0 degrees).
New in version 3.0: Enums
Methods
Returns true if the circle contains the
point
.Constructs a circle by 2 points on the circle.
Constructs a circle by 3 points on the circle.
Constructs a circle by 3 tangents on the circle (aka inscribed circle of a triangle).
Constructs a circle by a center point and a diameter.
Constructs a circle by a center point and another point.
Constructs a circle by an extent (aka bounding box /
QgsRectangle
).Calculates the inner tangent points between this circle and an
other
circle.Calculates the intersections points between this circle and an
other
circle.Constructs the smallest circle from 3 points.
The four quadrants of the ellipse.
Calculates the outer tangent points between this circle and an
other
circle.Returns the radius of the circle
Sets the radius of the circle
Inherited method.
Inherited method.
Calculates the tangent points between this circle and the point
p
.Returns a circular string from the circle.
Signals
Attributes
-
area
(self) → float¶
-
boundingBox
(self) → QgsRectangle¶
-
contains
(self, point: QgsPoint, epsilon: float = 1e-08) → bool¶ Returns true if the circle contains the
point
.
-
from2Points
(pt1: QgsPoint, pt2: QgsPoint) → QgsCircle¶ Constructs a circle by 2 points on the circle. The center point can have m value which is the result from the midpoint operation between
pt1
andpt2
. Z dimension is also supported and is retrieved from the first 3D point amongstpt1
andpt2
. The radius is calculated from the 2D distance betweenpt1
andpt2
. The azimuth is the angle betweenpt1
andpt2
.- Parameters
pt1 – First point.
pt2 – Second point.
-
from3Points
(pt1: QgsPoint, pt2: QgsPoint, pt3: QgsPoint, epsilon: float = 1e-08) → QgsCircle¶ Constructs a circle by 3 points on the circle. M value is dropped for the center point. Z dimension is supported and is retrieved from the first 3D point amongst
pt1
,pt2
andpt3
. The azimuth always takes the default value. If the points are colinear an empty circle is returned.- Parameters
pt1 – First point.
pt2 – Second point.
pt3 – Third point.
epsilon – Value used to compare point.
-
from3Tangents
(pt1_tg1: QgsPoint, pt2_tg1: QgsPoint, pt1_tg2: QgsPoint, pt2_tg2: QgsPoint, pt1_tg3: QgsPoint, pt2_tg3: QgsPoint, epsilon: float = 1e-08) → QgsCircle¶ Constructs a circle by 3 tangents on the circle (aka inscribed circle of a triangle). Z and m values are dropped for the center point. The azimuth always takes the default value.
- Parameters
pt1_tg1 – First point of the first tangent.
pt2_tg1 – Second point of the first tangent.
pt1_tg2 – First point of the second tangent.
pt2_tg2 – Second point of the second tangent.
pt1_tg3 – First point of the third tangent.
pt2_tg3 – Second point of the third tangent.
epsilon – Value used to compare point.
-
fromCenterDiameter
(center: QgsPoint, diameter: float, azimuth: float = 0) → QgsCircle¶ Constructs a circle by a center point and a diameter. The center point keeps z and m values from
center
.- Parameters
center – Center point.
diameter – Diameter of the circle.
azimuth – Azimuth of the circle.
-
fromCenterPoint
(center: QgsPoint, pt1: QgsPoint) → QgsCircle¶ Constructs a circle by a center point and another point. The center point keeps z and m values from
center
. Axes are calculated from the 2D distance betweencenter
andpt1
. The azimuth is the angle betweencenter
andpt1
.- Parameters
center – Center point.
pt1 – A point on the circle.
-
fromExtent
(pt1: QgsPoint, pt2: QgsPoint) → QgsCircle¶ Constructs a circle by an extent (aka bounding box /
QgsRectangle
). The center point can have m value which is the result from the midpoint operation betweenpt1
andpt2
. Z dimension is also supported and is retrieved from the first 3D point amongstpt1
andpt2
. Axes are calculated from the 2D distance betweenpt1
andpt2
. The azimuth always takes the default value.- Parameters
pt1 – First corner.
pt2 – Second corner.
-
innerTangents
(self, other: QgsCircle) → Tuple[int, QgsPointXY, QgsPointXY, QgsPointXY, QgsPointXY]¶ Calculates the inner tangent points between this circle and an
other
circle.The inner tangent points correspond to the points at which the two lines which are drawn so that they are tangential to both circles but on different sides, touching the circles and crossing each other.
The first tangent line is described by the points stored in
line1P1
andline1P2
, and the second line is described by the points stored inline2P1
andline2P2
.Returns the number of tangents (either 0 or 2).
Note that this method is 2D only and does not consider the z-value of the circle.
See also
New in version 3.6.
-
intersections
(self, other: QgsCircle, useZ: bool = False) → Tuple[int, QgsPoint, QgsPoint]¶ Calculates the intersections points between this circle and an
other
circle.If found, the intersection points will be stored in
intersection1
andintersection2
.By default this method does not consider any z values and instead treats the circles as 2-dimensional. If
useZ
is set to true, then an intersection will only occur if the z values of both circles are equal. In this case the points returned forintersection1
andintersection2
will contain the z value of the circle intersections.- Returns
number of intersection points found.
New in version 3.2.
-
minimalCircleFrom3Points
(pt1: QgsPoint, pt2: QgsPoint, pt3: QgsPoint, epsilon: float = 1e-08) → QgsCircle¶ Constructs the smallest circle from 3 points. Z and m values are dropped for the center point. The azimuth always takes the default value. If the points are colinear an empty circle is returned.
- Parameters
pt1 – First point.
pt2 – Second point.
pt3 – Third point.
epsilon – Value used to compare point.
-
northQuadrant
(self) → List[QgsPoint]¶ The four quadrants of the ellipse. They are oriented and started from North.
- Returns
quadrants defined by four points.
See also
quadrant()
-
outerTangents
(self, other: QgsCircle) → Tuple[int, QgsPointXY, QgsPointXY, QgsPointXY, QgsPointXY]¶ Calculates the outer tangent points between this circle and an
other
circle.The outer tangent points correspond to the points at which the two lines which are drawn so that they are tangential to both circles touch the circles.
The first tangent line is described by the points stored in
line1P1
andline1P2
, and the second line is described by the points stored inline2P1
andline2P2
.Returns the number of tangents (either 0 or 2).
Note that this method is 2D only and does not consider the z-value of the circle.
See also
New in version 3.2.
-
perimeter
(self) → float¶
-
radius
(self) → float¶ Returns the radius of the circle
-
setRadius
(self, radius: float)¶ Sets the radius of the circle
-
setSemiMajorAxis
(self, semiMajorAxis: float)¶ Inherited method. Use setRadius instead.
See also
See also
-
setSemiMinorAxis
(self, semiMinorAxis: float)¶ Inherited method. Use setRadius instead.
See also
See also
-
tangentToPoint
(self, p: QgsPointXY) → Tuple[bool, QgsPointXY, QgsPointXY]¶ Calculates the tangent points between this circle and the point
p
.If found, the tangent points will be stored in
pt1
andpt2
.Note that this method is 2D only and does not consider the z-value of the circle.
- Returns
true if tangent was found.
See also
New in version 3.2.
-
toCircularString
(self, oriented: bool = False) → QgsCircularString¶ Returns a circular string from the circle.
- Parameters
oriented – If oriented is true the start point is from azimuth instead from north.
-
toString
(self, pointPrecision: int = 17, radiusPrecision: int = 17, azimuthPrecision: int = 2) → str¶