  We suggest the azimuthal distribution of mean transverse (radial) rapidity of
the final state particles as a more direct measure of the transverse motion of
the source than the standard azimuthal multiplicity distribution. Using a
sample generated by the AMPT model with string melting, we demonstrate that the
azimuthal amplitude of the suggested distribution characterizes the anisotropic
radial flow, and coincides with the parameter of anisotropic radial rapidity
extracted from a generalized blast-wave parametrization.
