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Named Constants

psb_dupl_ovwrt_
  Duplicate coefficients should be overwritten (i.e. ignore duplications)
psb_dupl_add_
  Duplicate coefficients should be added;
psb_dupl_err_
  Duplicate coefficients should trigger an error conditino
psb_upd_dflt_
  Default update strategy for matrix coefficients;
psb_upd_srch_
  Update strategy based on search into the data structure;
psb_upd_perm_
  Update strategy based on additional permutation data (see tools routine description).