//! Calculate the distance from the currently set (m13Sq, m23Sq) point to the centre of the Dalitz plot (which is defined as the point where m12=m13=m23)
/*!
\return the distance to the DP centre
*/
Double_t distanceFromDPCentre() const;
//! Calculate the distance from a given (m13Sq, m23Sq) point to the centre of the Dalitz plot (which is defined as the point where m12=m13=m23)