example.cc File Reference

#include <cstdint>
#include <algorithm>
#include "gd.h"

Go to the source code of this file.

Classes
struct	features_and_source
struct	full_features_and_source

Namespaces
	VW

Functions
float	collision_cleanup (features &fs)
void	VW::copy_example_label (example *dst, example *src, size_t, void(*copy_label)(void *, void *))
void	VW::copy_example_metadata (bool, example *dst, example *src)
void	VW::copy_example_data (bool audit, example *dst, example *src)
void	VW::copy_example_data (bool audit, example *dst, example *src, size_t label_size, void(*copy_label)(void *, void *))
void	VW::move_feature_namespace (example *dst, example *src, namespace_index c)
void	vec_store (features_and_source &p, float fx, uint64_t fi)
feature *	VW::get_features (vw &all, example *ec, size_t &feature_map_len)
void	VW::return_features (feature *f)
void	vec_ffs_store (full_features_and_source &p, float fx, uint64_t fi)
flat_example *	flatten_example (vw &all, example *ec)
flat_example *	flatten_sort_example (vw &all, example *ec)
void	free_flatten_example (flat_example *fec)
example *	VW::alloc_examples (size_t, size_t count=1)
void	VW::dealloc_example (void(*delete_label)(void *), example &ec, void(*delete_prediction)(void *))
void	VW::finish_example (vw &, example &)
void	VW::clean_example (vw &, example &, bool rewind)
void	VW::finish_example (vw &all, multi_ex &ec_seq)
void	VW::return_multiple_example (vw &all, v_array< example *> &examples)

Function Documentation

collision_cleanup()

float collision_cleanup

(

features &

fs

)

Definition at line 11 of file example.cc.

References features::begin(), f, features_value_index_iterator::index(), and features_value_iterator::value().

Referenced by flatten_sort_example().

{
  uint64_t last_index = (uint64_t)-1;
  float sum_sq = 0.f;
  features::iterator pos = fs.begin();
  for (features::iterator& f : fs)
  {
    if (last_index == f.index())
      pos.value() += f.value();
    else
    {
      sum_sq += pos.value() * pos.value();
      ++pos;
      pos.value() = f.value();
      pos.index() = f.index();
      last_index = f.index();
    }
  }

  sum_sq += pos.value() * pos.value();
  fs.sum_feat_sq = sum_sq;
  ++pos;
  fs.truncate_to(pos);

  return sum_sq;
}

flatten_example()

flat_example* flatten_example	(	vw &	all,
		example *	ec
	)

Definition at line 152 of file example.cc.

References v_array< T >::begin(), example::example_counter, flat_example::example_counter, flat_example::fs, full_features_and_source::fs, example_predict::ft_offset, flat_example::ft_offset, example::l, flat_example::l, full_features_and_source::mask, parameters::mask(), parameters::not_null(), example::num_features, flat_example::num_features, polylabel::simple, v_array< T >::size(), full_features_and_source::stride_shift, parameters::stride_shift(), example::tag, flat_example::tag, flat_example::tag_len, label_data::weight, example::weight, and vw::weights.

Referenced by flatten_sort_example().

{
  flat_example& fec = calloc_or_throw<flat_example>();
  fec.l = ec->l;
  fec.l.simple.weight = ec->weight;

  fec.tag_len = ec->tag.size();
  if (fec.tag_len > 0)
  {
    fec.tag = calloc_or_throw<char>(fec.tag_len + 1);
    memcpy(fec.tag, ec->tag.begin(), fec.tag_len);
  }

  fec.example_counter = ec->example_counter;
  fec.ft_offset = ec->ft_offset;
  fec.num_features = ec->num_features;

  full_features_and_source ffs;
  ffs.stride_shift = all.weights.stride_shift();
  if (all.weights.not_null())  // TODO:temporary fix. all.weights is not initialized at this point in some cases.
    ffs.mask = (uint64_t)all.weights.mask() >> all.weights.stride_shift();
  else
    ffs.mask = (uint64_t)LONG_MAX >> all.weights.stride_shift();
  GD::foreach_feature<full_features_and_source, uint64_t, vec_ffs_store>(all, *ec, ffs);

  fec.fs = ffs.fs;

  return &fec;
}

flatten_sort_example()

flat_example* flatten_sort_example	(	vw &	all,
		example *	ec
	)

Definition at line 182 of file example.cc.

References collision_cleanup(), flatten_example(), flat_example::fs, vw::parse_mask, features::sort(), and flat_example::total_sum_feat_sq.

Referenced by learn(), memory_tree_ns::normalized_linear_prod(), and predict().

{
  flat_example* fec = flatten_example(all, ec);
  fec->fs.sort(all.parse_mask);
  fec->total_sum_feat_sq = collision_cleanup(fec->fs);
  return fec;
}

free_flatten_example()

void free_flatten_example

(

flat_example *

fec

)

Definition at line 190 of file example.cc.

References features::delete_v(), flat_example::fs, flat_example::tag, and flat_example::tag_len.

Referenced by memory_tree_ns::normalized_linear_prod(), and svm_example::~svm_example().

{
  // note: The label memory should be freed by by freeing the original example.
  if (fec)
  {
    fec->fs.delete_v();
    if (fec->tag_len > 0)
      free(fec->tag);
    free(fec);
  }
}

vec_ffs_store()

void vec_ffs_store	(	full_features_and_source &	p,
		float	fx,
		uint64_t	fi
	)

Definition at line 147 of file example.cc.

References full_features_and_source::fs, full_features_and_source::mask, features::push_back(), and full_features_and_source::stride_shift.

{
  p.fs.push_back(fx, (uint64_t)(fi >> p.stride_shift) & p.mask);
}

vec_store()

void vec_store	(	features_and_source &	p,
		float	fx,
		uint64_t	fi
	)

Definition at line 118 of file example.cc.

References features_and_source::feature_map, features_and_source::mask, v_array< T >::push_back(), and features_and_source::stride_shift.

{
  p.feature_map.push_back(feature(fx, (uint64_t)(fi >> p.stride_shift) & p.mask));
}