Similar to the Vector3D Classes and Point3D Classes , typedefs are defined to avoid exposing templated parameter to the users, for all 2D vectors based an double's and float's. To use them, one must include the header file Math/Vector2D.h or Math/Point2D.h. The following typedef's, defined in the header file Math/Vector2Dfwd.h, are available for the different instantiations of the template class ROOT::Math::DisplacementVector2D:

ROOT::Math::XYVector vector based on x,y coordinates (cartesian) in double precision
ROOT::Math::XYVectorF vector based on x,y coordinates (cartesian) in float precision
ROOT::Math::Polar2DVector vector based on r,phi coordinates (polar) in double precision
ROOT::Math::Polar2DVectorF vector based on r,phi coordinates (polar) in float precision

The typedef's, defined in the header file Math/Point2Dfwd.h, available for the different instantiations of the template class ROOT::Math::PoistionVector2D are:

ROOT::Math::XYPoint vector based on x,y coordinates (cartesian) in double precision
ROOT::Math::XYPointF vector based on x,y coordinates (cartesian) in float precision
ROOT::Math::Polar2DPoint vector based on r,phi coordinates (polar) in double precision
ROOT::Math::Polar2DPointF vector based on r,phi coordinates (polar) in float precision

Similar constructs, functions and operations available for the 3D vectors and points (see Vector3D Classes and Point3D Classes ) are available also for the 2D vector and points. No transformations or rotation classes are available for the 2D vectors.

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