Subgroup: other

Class: QgsTriangle

class qgis.core.QgsTriangle

Bases: qgis._core.QgsPolygon

QgsTriangle(p1: QgsPoint, p2: QgsPoint, p3: QgsPoint) Construct a QgsTriangle from three QgsPointV2.

Parameters:
  • p1 – first point
  • p2 – second point
  • p3 – third point

QgsTriangle(p1: QgsPointXY, p2: QgsPointXY, p3: QgsPointXY) Construct a QgsTriangle from three QgsPoint.

Parameters:
  • p1 – first point
  • p2 – second point
  • p3 – third point

QgsTriangle(p1: Union[QPointF, QPoint], p2: Union[QPointF, QPoint], p3: Union[QPointF, QPoint]) Construct a QgsTriangle from three QPointF.

Parameters:
  • p1 – first point
  • p2 – second point
  • p3 – third point

QgsTriangle(QgsTriangle)

Triangle geometry type.

New in version 3.0: Methods

addInteriorRing Inherited method not used.
altitudes An altitude is a segment (defined by a QgsLineString) from a vertex to the opposite side (or, if necessary, to the extension of the opposite side).
angles Returns the three angles of the triangle.
asGml3
bisectors The segment (defined by a QgsLineString) returned bisect the angle of a vertex to the opposite side.
boundary
calculateBoundingBox
childCount
childGeometry
childPoint
circumscribedCenter Center of the circumscribed circle of the triangle.
circumscribedCircle Circumscribed circle of the triangle.
circumscribedRadius Radius of the circumscribed circle of the triangle.
clear
clearCache
clone
createEmptyWithSameType
deleteVertex Inherited method not used.
fromWkb
fromWkt
geometryType
hasChildGeometries
inscribedCenter Center of the inscribed circle of the triangle.
inscribedCircle Inscribed circle of the triangle.
inscribedRadius Radius of the inscribed circle of the triangle.
insertVertex Inherited method not used.
isDegenerate Convenient method checking if the geometry is degenerate (have duplicate or colinear point(s)).
isEquilateral Is the triangle equilateral (three sides with the same length)?
isIsocele Is the triangle isocele (two sides with the same length)?
isRight Is the triangle right-angled?
isScalene Is the triangle scalene (all sides have differen lengths)?
lengths Returns the three lengths of the triangle.
medial Medial (or midpoint) triangle of a triangle ABC is the triangle with vertices at the midpoints of the triangle’s sides.
medians A median is a segment (defined by a QgsLineString) from a vertex to the midpoint of the opposite side.
moveVertex
orthocenter An orthocenter is the point of intersection of the altitudes of a triangle.
setExteriorRing
setZMTypeFromSubGeometry
surfaceToPolygon
toCurveType
vertexAt Returns coordinates of a vertex.

Signals

Attributes

addInteriorRing(self, ring: QgsCurve)

Inherited method not used. You cannot add an interior ring into a triangle.

altitudes(self) → object

An altitude is a segment (defined by a QgsLineString) from a vertex to the opposite side (or, if necessary, to the extension of the opposite side).

Returns:Three altitudes from this triangle.

An empty list is returned for empty triangle. * Example: .. code-block:: python

tri = QgsTriangle( QgsPoint( 0, 0 ), QgsPoint( 0, 5 ), QgsPoint( 5, 5 ) ) [alt.asWkt() for alt in tri.altitudes()] # [‘LineString (0 0, 0 5)’, ‘LineString (0 5, 2.5 2.5)’, ‘LineString (5 5, 0 5)’] QgsTriangle().altitudes() # []
angles(self) → List[float]

Returns the three angles of the triangle.

Returns:Angles in radians of triangle ABC where angle BAC is at 0, angle ABC is at 1, angle BCA is at 2.

An empty list is returned for empty triangle. * Example: .. code-block:: python

tri = QgsTriangle( QgsPoint( 0, 0 ), QgsPoint( 0, 5 ), QgsPoint( 5, 5 ) ) [math.degrees(i) for i in tri.angles()] # [45.0, 90.0, 45.0] QgsTriangle().angles() # []
asGml3(self, doc: QDomDocument, precision: int = 17, ns: str = '') → QDomElement
bisectors(self, lengthTolerance: float = 0.0001) → List[QgsLineString]

The segment (defined by a QgsLineString) returned bisect the angle of a vertex to the opposite side.

Parameters:lengthTolerance – The tolerance to use.
Returns:Three angle bisector from this triangle.

An empty list is returned for empty triangle. * Example: .. code-block:: python

tri = QgsTriangle( QgsPoint( 0, 0 ), QgsPoint( 0, 5 ), QgsPoint( 5, 5 ) ) [bis.asWkt() for bis in tri.bisectors()] # [‘LineString (0 0, 2.07106781186547462 5)’, ‘LineString (0 5, 2.5 2.5)’, ‘LineString (5 5, 0 2.92893218813452538)’] QgsTriangle().bisectors() # []
boundary(self) → QgsCurve
calculateBoundingBox()
childCount()
childGeometry()
childPoint()
circumscribedCenter(self) → QgsPoint

Center of the circumscribed circle of the triangle.

Returns:The center of the circumscribed circle of the triangle.

An empty point is returned for empty triangle. * Example: .. code-block:: python

tri = QgsTriangle( QgsPoint( 0, 0 ), QgsPoint( 0, 5 ), QgsPoint( 5, 5 ) ) tri.circumscribedCenter().asWkt() # ‘Point (2.5 2.5)’ QgsTriangle().circumscribedCenter().asWkt() # ‘Point (0 0)’
circumscribedCircle(self) → QgsCircle

Circumscribed circle of the triangle.

Returns:The circumbscribed of the triangle with a QgsCircle.

An empty circle is returned for empty triangle. Example: .. code-block:: python

tri = QgsTriangle( QgsPoint( 0, 0 ), QgsPoint( 0, 5 ), QgsPoint( 5, 5 ) ) tri.circumscribedCircle() # QgsCircle(Point (2.5 2.5), 3.5355339059327378, 0) QgsTriangle().circumscribedCircle() # QgsCircle()
circumscribedRadius(self) → float

Radius of the circumscribed circle of the triangle.

Returns:The radius of the circumscribed circle of the triangle.

0.0 is returned for empty triangle. * Example: .. code-block:: python

tri = QgsTriangle( QgsPoint( 0, 0 ), QgsPoint( 0, 5 ), QgsPoint( 5, 5 ) ) tri.circumscribedRadius() # 3.5355339059327378 QgsTriangle().circumscribedRadius() # 0.0
clear(self)
clearCache()
clone(self) → QgsTriangle
createEmptyWithSameType(self) → QgsTriangle
deleteVertex(self, position: QgsVertexId) → bool

Inherited method not used. You cannot delete or insert a vertex directly. Returns always false.

fromWkb(self, wkbPtr: QgsConstWkbPtr) → bool
fromWkt(self, wkt: str) → bool
geometryType(self) → str
hasChildGeometries()
inscribedCenter(self) → QgsPoint

Center of the inscribed circle of the triangle. Z dimension is supported and is retrieved from the first 3D point amongst vertices.

Returns:The center of the inscribed circle of the triangle.

An empty point is returned for empty triangle. * Example: .. code-block:: python

tri = QgsTriangle( QgsPoint( 0, 0 ), QgsPoint( 0, 5 ), QgsPoint( 5, 5 ) ) tri.inscribedCenter().asWkt() # ‘Point (1.46446609406726225 3.53553390593273775)’ QgsTriangle().inscribedCenter().asWkt() # ‘Point (0 0)’
inscribedCircle(self) → QgsCircle

Inscribed circle of the triangle.

Returns:The inscribed of the triangle with a QgsCircle.

An empty circle is returned for empty triangle. Example: .. code-block:: python

tri = QgsTriangle( QgsPoint( 0, 0 ), QgsPoint( 0, 5 ), QgsPoint( 5, 5 ) ) tri.inscribedCircle() # QgsCircle(Point (1.46446609406726225 3.53553390593273775), 1.4644660940672622, 0) QgsTriangle().inscribedCircle() # QgsCircle()
inscribedRadius(self) → float

Radius of the inscribed circle of the triangle.

Returns:The radius of the inscribed circle of the triangle.

0.0 is returned for empty triangle. * Example: .. code-block:: python

tri = QgsTriangle( QgsPoint( 0, 0 ), QgsPoint( 0, 5 ), QgsPoint( 5, 5 ) ) tri.inscribedRadius() # 1.4644660940672622 QgsTriangle().inscribedRadius() # 0.0
insertVertex(self, position: QgsVertexId, vertex: QgsPoint) → bool

Inherited method not used. You cannot delete or insert a vertex directly. Returns always false.

isDegenerate(self) → bool

Convenient method checking if the geometry is degenerate (have duplicate or colinear point(s)).

Returns:True if the triangle is degenerate or empty, otherwise false.

Example: .. code-block:: python

tri = QgsTriangle() tri.isDegenerate() # True tri = QgsTriangle( QgsPoint( 0, 0 ), QgsPoint( 0, 5 ), QgsPoint( 5, 5 ) ) tri.isDegenerate() # False tri = QgsTriangle( QgsPoint( 0, 0 ), QgsPoint( 5, 5 ), QgsPoint( 10, 10 ) ) tri.isDegenerate() # True tri = QgsTriangle( QgsPoint( 0, 0 ), QgsPoint( 0, 0 ), QgsPoint( 5, 5 ) ) tri.isDegenerate() # True
isEquilateral(self, lengthTolerance: float = 0.0001) → bool

Is the triangle equilateral (three sides with the same length)?

Parameters:lengthTolerance – The tolerance to use
Returns:True or False. Always false for empty triangle.
  • Example:
tri = QgsTriangle( QgsPoint( 10, 10 ), QgsPoint( 16, 10 ), QgsPoint( 13, 15.1962 ) )
tri.lengths()
# [6.0, 6.0000412031918575, 6.0000412031918575]
tri.isEquilateral()
# True
# All lengths are close to 6.0
QgsTriangle().isEquilateral()
# False
isIsocele(self, lengthTolerance: float = 0.0001) → bool

Is the triangle isocele (two sides with the same length)?

Parameters:lengthTolerance – The tolerance to use
Returns:True or False. Always false for empty triangle.
  • Example:
tri = QgsTriangle( QgsPoint( 0, 0 ), QgsPoint( 0, 5 ), QgsPoint( 5, 5 ) )
tri.lengths()
# [5.0, 5.0, 7.0710678118654755]
tri.isIsocele()
# True
# length of [AB] == length of [BC]
QgsTriangle().isIsocele()
# False
isRight(self, angleTolerance: float = 0.0001) → bool

Is the triangle right-angled?

Parameters:angleTolerance – The tolerance to use
Returns:True or False. Always false for empty triangle.
  • Example:
tri = QgsTriangle( QgsPoint( 0, 0 ), QgsPoint( 0, 5 ), QgsPoint( 5, 5 ) )
[math.degrees(i) for i in tri.angles()]
# [45.0, 90.0, 45.0]
tri.isRight()
# True
# angle of ABC == 90
QgsTriangle().isRight()
# False
isScalene(self, lengthTolerance: float = 0.0001) → bool

Is the triangle scalene (all sides have differen lengths)?

Parameters:lengthTolerance – The tolerance to use
Returns:True or False. Always false for empty triangle.
  • Example:
tri = QgsTriangle( QgsPoint( 7.2825, 4.2368 ), QgsPoint( 13.0058, 3.3218 ), QgsPoint( 9.2145, 6.5242 ) )
tri.lengths()
# [5.795980321740233, 4.962793714229921, 2.994131386562721]
tri.isScalene()
# True
# All lengths are different
QgsTriangle().isScalene()
# False
lengths(self) → List[float]

Returns the three lengths of the triangle.

Returns:Lengths of triangle ABC where [AB] is at 0, [BC] is at 1, [CA] is at 2.

An empty list is returned for empty triangle. * Example: .. code-block:: python

tri = QgsTriangle( QgsPoint( 0, 0 ), QgsPoint( 0, 5 ), QgsPoint( 5, 5 ) ) tri.lengths() # [5.0, 5.0, 7.0710678118654755] QgsTriangle().lengths() # []
medial(self) → QgsTriangle

Medial (or midpoint) triangle of a triangle ABC is the triangle with vertices at the midpoints of the triangle’s sides.

Returns:The medial from this triangle.

An empty triangle is returned for empty triangle. * Example: .. code-block:: python

tri = QgsTriangle( QgsPoint( 0, 0 ), QgsPoint( 0, 5 ), QgsPoint( 5, 5 ) ) tri.medial().asWkt() # ‘Triangle ((0 2.5, 2.5 5, 2.5 2.5, 0 2.5))’ QgsTriangle().medial().asWkt() # ‘Triangle ( )’
medians(self) → List[QgsLineString]

A median is a segment (defined by a QgsLineString) from a vertex to the midpoint of the opposite side.

Returns:Three medians from this triangle.

An empty list is returned for empty triangle. * Example: .. code-block:: python

tri = QgsTriangle( QgsPoint( 0, 0 ), QgsPoint( 0, 5 ), QgsPoint( 5, 5 ) ) [med.asWkt() for med in tri.medians()] # [‘LineString (0 0, 2.5 5)’, ‘LineString (0 5, 2.5 2.5)’, ‘LineString (5 5, 0 2.5)’] QgsTriangle().medians() # []
moveVertex(self, vId: QgsVertexId, newPos: QgsPoint) → bool
orthocenter(self, lengthTolerance: float = 0.0001) → QgsPoint

An orthocenter is the point of intersection of the altitudes of a triangle.

Parameters:lengthTolerance – The tolerance to use
Returns:The orthocenter of the triangle.

An empty point is returned for empty triangle. * Example: .. code-block:: python

tri = QgsTriangle( QgsPoint( 0, 0 ), QgsPoint( 0, 5 ), QgsPoint( 5, 5 ) ) tri.orthocenter().asWkt() # ‘Point (0 5)’ QgsTriangle().orthocenter().asWkt() # ‘Point (0 0)’
setExteriorRing(self, ring: QgsCurve)
setZMTypeFromSubGeometry()
surfaceToPolygon(self) → QgsPolygon
toCurveType(self) → QgsCurvePolygon
vertexAt(self, atVertex: int) → QgsPoint

Returns coordinates of a vertex.

Parameters:atVertex – index of the vertex
Returns:Coordinates of the vertex or QgsPoint(0,0) on error (atVertex < 0 or > 3).