code: func (model *Model) SetDivergenceThreshold(val int) {
  	model.Lock()
  	model.SuffDivergenceThreshold = val
  	model.Unlock()
  }
docs: // Optionally set the suffix array divergence threshold. This is
  // the number of query training steps between rebuilds of the
  // suffix array. A low number will be more accurate but will use
  // resources and create more garbage.