|  | Home · All Classes · Modules

# QPointF Class Reference
[QtCore module]

The QPointF class defines a point in the plane using floating point precision. More...

### Methods

- __init__ (self)
- __init__ (self, QPainterPath.Element)
- __init__ (self, float xpos, float ypos)
- __init__ (self, QPoint p)
- __init__ (self, QPointF)
- bool isNull (self)
- float manhattanLength (self)
- setX (self, float xpos)
- setY (self, float ypos)
- QPoint toPoint (self)
- float x (self)
- float y (self)

### Special Methods

- QPointF __mul__ (self, QMatrix m)
- QPointF __mul__ (self, QMatrix4x4 matrix)
- QPointF __mul__ (self, QTransform m)
- QPointF __add__ (self, QPointF p2)
- int __bool__ (self)
- QPointF __div__ (self, float c)
- bool __eq__ (self, QPointF p2)
- QPointF __iadd__ (self, QPointF p)
- QPointF __idiv__ (self, float c)
- QPointF __imul__ (self, float c)
- QPointF __isub__ (self, QPointF p)
- QPointF __mul__ (self, float c)
- bool __ne__ (self, QPointF p2)
- QPointF __neg__ (self)
- str __repr__ (self)
- QPointF __sub__ (self, QPointF p2)

## Detailed Description

This class can be pickled.

The QPointF class defines a point in the plane using floating point precision.

A point is specified by a x coordinate and an y coordinate which can be accessed using the x() and y() functions. The coordinates of the point are specified using floating point numbers for accuracy. The isNull() function returns true if both x and y are set to 0.0. The coordinates can be set (or altered) using the setX() and setY() functions, or alternatively the rx() and ry() functions which return references to the coordinates (allowing direct manipulation).

Given a point p, the following statements are all equivalent:

     QPointF p;

     p.setX(p.x() + 1.0);
     p += QPointF(1.0, 0.0);
     p.rx()++;

A QPointF object can also be used as a vector: Addition and subtraction are defined as for vectors (each component is added separately). A QPointF object can also be divided or multiplied by an `int` or a `qreal`.

In addition, the QPointF class provides a constructor converting a QPoint object into a QPointF object, and a corresponding toPoint() function which returns a QPoint copy of this point. Finally, QPointF objects can be streamed as well as compared.

## Method Documentation

### QPointF.__init__ (self)

Constructs a null point, i.e. with coordinates (0.0, 0.0)

See also isNull().

### QPointF.__init__ (self, QPainterPath.Element)

This method is only available if the QtGui module is imported.

Constructs a null point, i.e. with coordinates (0.0, 0.0)

See also isNull().

### QPointF.__init__ (self, float xpos, float ypos)

Constructs a copy of the given point.

See also toPoint().

### QPointF.__init__ (self, QPoint p)

Constructs a point with the given coordinates (x, y).

See also setX() and setY().

### QPointF.__init__ (self, QPointF)

### bool QPointF.isNull (self)

Returns true if both the x and y coordinates are set to +0.0; otherwise returns false.

Note: Since this function treats +0.0 and -0.0 differently, points with zero-valued coordinates where either or both values have a negative sign are not defined to be null points.

### float QPointF.manhattanLength (self)

Returns the sum of the absolute values of x() and y(), traditionally known as the "Manhattan length" of the vector from the origin to the point.

This function was introduced in Qt 4.6.

See also QPoint.manhattanLength().

### QPointF.setX (self, float xpos)

Sets the x coordinate of this point to the given x coordinate.

See also x() and setY().

### QPointF.setY (self, float ypos)

Sets the y coordinate of this point to the given y coordinate.

See also y() and setX().

### QPoint QPointF.toPoint (self)

Rounds the coordinates of this point to the nearest integer, and returns a QPoint object with the rounded coordinates.

See also QPointF().

### float QPointF.x (self)

Returns the x-coordinate of this point.

See also setX() and rx().

### float QPointF.y (self)

Returns the y-coordinate of this point.

See also setY() and ry().

### QPointF __mul__ (self, QMatrix m)

This method is only available if the QtGui module is imported.

### QPointF __mul__ (self, QMatrix4x4 matrix)

This method is only available if the QtGui module is imported.

### QPointF __mul__ (self, QTransform m)

This method is only available if the QtGui module is imported.

### QPointF QPointF.__add__ (self, QPointF p2)

### int QPointF.__bool__ (self)

### QPointF QPointF.__div__ (self, float c)

### bool QPointF.__eq__ (self, QPointF p2)

### QPointF QPointF.__iadd__ (self, QPointF p)

### QPointF QPointF.__idiv__ (self, float c)

### QPointF QPointF.__imul__ (self, float c)

### QPointF QPointF.__isub__ (self, QPointF p)

### QPointF QPointF.__mul__ (self, float c)

### bool QPointF.__ne__ (self, QPointF p2)

### QPointF QPointF.__neg__ (self)

### str QPointF.__repr__ (self)

### QPointF QPointF.__sub__ (self, QPointF p2)