Function sequant::mbpt::interval_excitation_type_qns

Function Documentation

qns_t sequant::mbpt::interval_excitation_type_qns(std::size_t k, IndexSpace::QuantumNumbers SQN = Spin::any)

Constructs quantum numbers for an excitation operator based on the defined context. Sometimes we want to guarantee that a qns has an interval from 0 to k regardless of base spaces.

Parameters:
  • k – the rank of the operator, QN has the interval from 0 to k

  • SQN – the spin quantum number