Implemented a State data structure, which derives from Particle and has an index. This allows distinguishing particles in the final state if they are equal.
It also made it possible to generalize the dynamics builders. They were defined in the notebooks so far, but have been generalized and moved to a ampform_dpd.dynamics.builder module. See also https://github.com/ComPWA/ampform-dpd/pull/113.
A helper function permutate_equal_final_states() was added for QRules state transitions with equal particles in the final state.
Closes #108
Statedata structure, which derives fromParticleand has anindex. This allows distinguishing particles in the final state if they are equal.ampform_dpd.dynamics.buildermodule. See also https://github.com/ComPWA/ampform-dpd/pull/113.permutate_equal_final_states()was added for QRules state transitions with equal particles in the final state.