SequenceTask_DemoLDF Namespace Reference

Classes
struct	task_data

Functions
void	initialize (Search::search &sch, size_t &num_actions, options_i &)
void	finish (Search::search &sch)
void	my_update_example_indicies (Search::search &sch, bool, example *ec, uint64_t mult_amount, uint64_t plus_amount)
void	run (Search::search &sch, multi_ex &ec)

Variables
Search::search_task	task = {"sequence_demoldf", run, initialize, finish, nullptr, nullptr}

Function Documentation

finish()

void SequenceTask_DemoLDF::finish

(

Search::search &

sch

)

Definition at line 402 of file search_sequencetask.cc.

References a, COST_SENSITIVE::cs_label, VW::dealloc_example(), CB::delete_label(), Search::search::get_task_data(), SequenceTask_DemoLDF::task_data::ldf_examples, and SequenceTask_DemoLDF::task_data::num_actions.

{
  task_data* data = sch.get_task_data<task_data>();
  for (size_t a = 0; a < data->num_actions; a++) VW::dealloc_example(CS::cs_label.delete_label, data->ldf_examples[a]);
  free(data->ldf_examples);
  free(data);
}

initialize()

void SequenceTask_DemoLDF::initialize	(	Search::search &	sch,
		size_t &	num_actions,
		options_i &
	)

Definition at line 379 of file search_sequencetask.cc.

References a, VW::alloc_examples(), Search::AUTO_CONDITION_FEATURES, Search::AUTO_HAMMING_LOSS, COST_SENSITIVE::label::costs, polylabel::cs, COST_SENSITIVE::cs_label, label_parser::default_label, Search::search::get_vw_pointer_unsafe(), example_predict::interactions, vw::interactions, Search::IS_LDF, example::l, SequenceTask_DemoLDF::task_data::ldf_examples, SequenceTask_DemoLDF::task_data::num_actions, Search::search::set_options(), and Search::search::set_task_data().

{
  CS::wclass default_wclass = {0., 0, 0., 0.};

  example* ldf_examples = VW::alloc_examples(sizeof(CS::label), num_actions);
  for (size_t a = 0; a < num_actions; a++)
  {
    CS::label& lab = ldf_examples[a].l.cs;
    CS::cs_label.default_label(&lab);
    lab.costs.push_back(default_wclass);
    ldf_examples[a].interactions = &sch.get_vw_pointer_unsafe().interactions;
  }

  task_data* data = &calloc_or_throw<task_data>();
  data->ldf_examples = ldf_examples;
  data->num_actions = num_actions;

  sch.set_task_data<task_data>(data);
  sch.set_options(Search::AUTO_CONDITION_FEATURES |  // automatically add history features to our examples, please
      Search::AUTO_HAMMING_LOSS |  // please just use hamming loss on individual predictions -- we won't declare loss
      Search::IS_LDF);             // we generate ldf examples
}

my_update_example_indicies()

void SequenceTask_DemoLDF::my_update_example_indicies	(	Search::search &	sch,
		bool	,
		example *	ec,
		uint64_t	mult_amount,
		uint64_t	plus_amount
	)

Definition at line 411 of file search_sequencetask.cc.

References Search::search::get_stride_shift().

Referenced by run().

{
  size_t ss = sch.get_stride_shift();
  for (features& fs : *ec)
    for (feature_index& idx : fs.indicies) idx = (((idx >> ss) * mult_amount) + plus_amount) << ss;
}

run()

void SequenceTask_DemoLDF::run	(	Search::search &	sch,
		multi_ex &	ec
	)

Definition at line 419 of file search_sequencetask.cc.

References a, VW::copy_example_data(), COST_SENSITIVE::label::costs, polylabel::cs, Search::search::get_history_length(), Search::search::get_task_data(), example::l, SequenceTask_DemoLDF::task_data::ldf_examples, my_update_example_indicies(), SequenceTask_DemoLDF::task_data::num_actions, Search::search::output(), predict(), and Search::search::predictNeedsExample().

{
  task_data* data = sch.get_task_data<task_data>();
  Search::predictor P(sch, (ptag)0);
  for (ptag i = 0; i < ec.size(); i++)
  {
    for (uint32_t a = 0; a < data->num_actions; a++)
    {
      if (sch.predictNeedsExample())  // we can skip this work if `predict` won't actually use the example data
      {
        VW::copy_example_data(false, &data->ldf_examples[a], ec[i]);  // copy but leave label alone!
        // now, offset it appropriately for the action id
        my_update_example_indicies(sch, true, &data->ldf_examples[a], 28904713, 4832917 * (uint64_t)a);
      }

      // regardless of whether the example is needed or not, the class info is needed
      CS::label& lab = data->ldf_examples[a].l.cs;
      // need to tell search what the action id is, so that it can add history features correctly!
      lab.costs[0].x = 0.;
      lab.costs[0].class_index = a + 1;
      lab.costs[0].partial_prediction = 0.;
      lab.costs[0].wap_value = 0.;
    }

    action oracle = ec[i]->l.multi.label - 1;
    action pred_id = P.set_tag((ptag)(i + 1))
                         .set_input(data->ldf_examples, data->num_actions)
                         .set_oracle(oracle)
                         .set_condition_range(i, sch.get_history_length(), 'p')
                         .predict();
    action prediction = pred_id + 1;  // or ldf_examples[pred_id]->ld.costs[0].weight_index

    if (sch.output().good())
      sch.output() << prediction << ' ';
  }
}

Variable Documentation

task

Search::search_task SequenceTask_DemoLDF::task = {"sequence_demoldf", run, initialize, finish, nullptr, nullptr}

Definition at line 29 of file search_sequencetask.cc.