multilabel_oaa.cc File Reference

#include <sstream>
#include <float.h>
#include "reductions.h"
#include "vw.h"

Go to the source code of this file.

Classes
struct	multi_oaa

Functions
template<bool is_learn>
void	predict_or_learn (multi_oaa &o, LEARNER::single_learner &base, example &ec)
void	finish_example (vw &all, multi_oaa &, example &ec)
LEARNER::base_learner *	multilabel_oaa_setup (options_i &options, vw &all)

Function Documentation

finish_example()

void finish_example	(	vw &	all,
		multi_oaa &	,
		example &	ec
	)

Definition at line 52 of file multilabel_oaa.cc.

References VW::finish_example(), and MULTILABEL::output_example().

{
  MULTILABEL::output_example(all, ec);
  VW::finish_example(all, ec);
}

multilabel_oaa_setup()

LEARNER::base_learner* multilabel_oaa_setup	(	options_i &	options,
		vw &	all
	)

Definition at line 58 of file multilabel_oaa.cc.

References VW::config::options_i::add_and_parse(), LEARNER::as_singleline(), label_parser::delete_label, vw::delete_prediction, VW::finish_example(), LEARNER::init_learner(), vw::label_type, parser::lp, LEARNER::make_base(), VW::config::make_option(), label_type::multi, MULTILABEL::multilabel, prediction_type::multilabels, vw::p, LEARNER::learner< T, E >::set_finish_example(), setup_base(), and VW::config::options_i::was_supplied().

Referenced by parse_reductions().

{
  auto data = scoped_calloc_or_throw<multi_oaa>();
  option_group_definition new_options("Multilabel One Against All");
  new_options.add(make_option("multilabel_oaa", data->k).keep().help("One-against-all multilabel with <k> labels"));
  options.add_and_parse(new_options);

  if (!options.was_supplied("multilabel_oaa"))
    return nullptr;

  LEARNER::learner<multi_oaa, example>& l = LEARNER::init_learner(data, as_singleline(setup_base(options, all)),
      predict_or_learn<true>, predict_or_learn<false>, data->k, prediction_type::multilabels);
  l.set_finish_example(finish_example);
  all.p->lp = MULTILABEL::multilabel;
  all.label_type = label_type::multi;
  all.delete_prediction = MULTILABEL::multilabel.delete_label;

  return make_base(l);
}

predict_or_learn()

template<bool is_learn>

void predict_or_learn	(	multi_oaa &	o,
		LEARNER::single_learner &	base,
		example &	ec
	)

Definition at line 19 of file multilabel_oaa.cc.

References v_array< T >::clear(), multi_oaa::k, example::l, label_data::label, MULTILABEL::labels::label_v, LEARNER::learner< T, E >::learn(), prediction_type::multilabels, polylabel::multilabels, polyprediction::multilabels, example::pred, LEARNER::learner< T, E >::predict(), v_array< T >::push_back(), polyprediction::scalar, polylabel::simple, and v_array< T >::size().

{
  MULTILABEL::labels multilabels = ec.l.multilabels;
  MULTILABEL::labels preds = ec.pred.multilabels;
  preds.label_v.clear();

  ec.l.simple = {FLT_MAX, 1.f, 0.f};
  uint32_t multilabel_index = 0;
  for (uint32_t i = 0; i < o.k; i++)
  {
    if (is_learn)
    {
      ec.l.simple.label = -1.f;
      if (multilabels.label_v.size() > multilabel_index && multilabels.label_v[multilabel_index] == i)
      {
        ec.l.simple.label = 1.f;
        multilabel_index++;
      }
      base.learn(ec, i);
    }
    else
      base.predict(ec, i);
    if (ec.pred.scalar > 0.)
      preds.label_v.push_back(i);
  }
  if (is_learn && multilabel_index < multilabels.label_v.size())
    std::cout << "label " << multilabels.label_v[multilabel_index] << " is not in {0," << o.k - 1
              << "} This won't work right." << std::endl;

  ec.pred.multilabels = preds;
  ec.l.multilabels = multilabels;
}