Calculates pairwise transverse-momentum (pt) weighted distances between two sets of 4-momenta. The pt weighting is raised to the power given by pt_exp.

Parameters:¶

parton_pmu : MomentumArray¶

Sets of 4-momenta for which to calculate the pairwise delta R.

hadron_pmu : MomentumArray¶

Sets of 4-momenta for which to calculate the pairwise delta R.

pt_exp : float¶

Power associated with pt weighting. Default is -0.1.

Returns:¶

dists – Distance matrix between parton_pmu and hadron_pmu, whose number of rows and columns equal to the input sizes, respectively.

Return type:¶

ndarray[float64]

Notes

If using this function as a distance strategy when forming clusters, non-negative values of pt_exp will result in an IR unsafe algorithm.

This function was created to be a distance strategy for select.partition_descendants(). The intent of these routines has not yet fully stabilised, so the implementation and function signature may change in future releases.