algo::classification::OnevAll< MODEL, T > Class Template Reference

Public Member Functions
	OnevAll ()=default
template<class... Args>
	OnevAll (const size_t &num_class, const Args &... args)
template<class... Args>
	OnevAll (const arma::Mat< T > &inputs, const arma::Row< size_t > &labels, const size_t &num_class, const Args &... args)
template<class... Args>
void	Train (const arma::Mat< T > &inputs, const arma::Row< size_t > &labels, const Args &... args)
template<class... Args>
void	Train (const arma::Mat< T > &inputs, const arma::Row< size_t > &labels)
void	Classify (const arma::Mat< T > &inputs, arma::Row< size_t > &preds) const
void	Classify (const arma::Mat< T > &inputs, arma::Row< size_t > &preds, arma::Mat< T > &probs) const
T	ComputeError (const arma::Mat< T > &inputs, const arma::Row< size_t > &labels)
T	ComputeAccuracy (const arma::Mat< T > &inputs, const arma::Row< size_t > &labels)
template<typename Archive >
void	serialize (Archive &ar, const unsigned int)

Public Attributes
std::vector< MODEL >	models_

Detailed Description

template<class MODEL, class T = DTYPE>
class algo::classification::OnevAll< MODEL, T >

Definition at line 22 of file multiclass.h.

Constructor & Destructor Documentation

OnevAll() [1/3]

template<class MODEL , class T = DTYPE>

algo::classification::OnevAll< MODEL, T >::OnevAll ( )

default

Non-working model

OnevAll() [2/3]

template<class MODEL , class T >

template<class... Args>

algo::classification::OnevAll< MODEL, T >::OnevAll	(	const size_t &	num_class,
		const Args &...	args
	)

Parameters

args	: parameters for the model

Definition at line 19 of file multiclass_impl.h.

                                                                        :
  nclass_(num_class)
{ 
  models_.resize(num_class);
  for(size_t i=0;i<num_class;i++)
    models_[i] = MODEL(args...);
}

OnevAll() [3/3]

template<class MODEL , class T >

template<class... Args>

algo::classification::OnevAll< MODEL, T >::OnevAll	(	const arma::Mat< T > &	inputs,
		const arma::Row< size_t > &	labels,
		const size_t &	num_class,
		const Args &...	args
	)

Parameters

inputs	: X
labels	: y
args	: parameters for the model

Definition at line 29 of file multiclass_impl.h.

                                                 : nclass_(num_class)
{ 
  unq_ = arma::unique(labels).eval();
  if (unq_.n_elem == 1)
    oneclass_ = true;
 
  unclass_ = unq_.n_elem;
  models_.resize(unclass_);
 
  for(size_t i=0;i<unclass_;i++)
    models_[i] = MODEL(args...);
 
  Train(inputs, labels, args...);
  
} 

Member Function Documentation

Classify() [1/2]

template<class MODEL , class T >

void algo::classification::OnevAll< MODEL, T >::Classify	(	const arma::Mat< T > &	inputs,
		arma::Row< size_t > &	preds
	)		const

Parameters

inputs	: X*
preds	: y*

Definition at line 89 of file multiclass_impl.h.

{
  arma::Mat<T> probs;
  Classify(inputs, preds, probs);
}

Classify() [2/2]

template<class MODEL , class T >

void algo::classification::OnevAll< MODEL, T >::Classify	(	const arma::Mat< T > &	inputs,
		arma::Row< size_t > &	preds,
		arma::Mat< T > &	probs
	)		const

Parameters

inputs	: X*
preds	: y*
probs	: p*

Definition at line 97 of file multiclass_impl.h.

{
  probs.resize(nclass_,inputs.n_cols);
  preds.resize(inputs.n_cols);
  if (!oneclass_)
  {
    for(size_t i=0;i<unclass_;i++)
    {
      arma::Row<size_t> temp;
      arma::Mat<T> tprobs;
      models_[i].Classify(inputs,temp,tprobs);
      probs.row(unq_(i)) = tprobs.row(1);
    }
    preds = arma::conv_to<arma::Row<size_t>>::from(arma::index_max(arma::abs(probs),0));
 
    // We cannot decide and randomly assign a class
  
    arma::uvec cantdecide = arma::find(arma::sum(probs,0) == 0);
    arma::uvec randomsel = arma::randi<arma::uvec>(cantdecide.n_elem,
                            arma::distr_param(0,nclass_-1));
    probs.elem(randomsel+ cantdecide*nclass_).ones();
    probs = probs.each_row() / arma::sum(probs,0);
 
  }
  else
    preds.fill(unq_[0]);
}

ComputeAccuracy()

template<class MODEL , class T >

T algo::classification::OnevAll< MODEL, T >::ComputeAccuracy	(	const arma::Mat< T > &	inputs,
		const arma::Row< size_t > &	labels
	)

Parameters

inputs	: X
labels	: y

Definition at line 138 of file multiclass_impl.h.

{
  return 1.-ComputeError(inputs,labels);
}

ComputeError()

template<class MODEL , class T >

T algo::classification::OnevAll< MODEL, T >::ComputeError	(	const arma::Mat< T > &	inputs,
		const arma::Row< size_t > &	labels
	)

Parameters

inputs	: X
labels	: y

Definition at line 128 of file multiclass_impl.h.

{
  arma::Row<size_t> predictions;
  Classify(inputs, predictions);
  arma::Row<size_t> temp =  predictions - labels; 
  return (arma::accu(temp != 0))/T(predictions.n_elem);
}

serialize()

template<class MODEL , class T = DTYPE>

template<typename Archive >

void algo::classification::OnevAll< MODEL, T >::serialize ( Archive &  ar, const unsigned int    )

inline

Serialize the model.

Definition at line 100 of file multiclass.h.

  {
    ar (  cereal::make_nvp("nclass",nclass_),
          cereal::make_nvp("unclass",unclass_),
          cereal::make_nvp("unq",unq_),
          cereal::make_nvp("models",models_),
          cereal::make_nvp("oneclass",oneclass_));
  }

Train() [1/2]

template<class MODEL , class T >

template<class... Args>

void algo::classification::OnevAll< MODEL, T >::Train	(	const arma::Mat< T > &	inputs,
		const arma::Row< size_t > &	labels
	)

Parameters

inputs	: X
labels	: y
args	: parameters for the model

Definition at line 50 of file multiclass_impl.h.

{ 
  unq_ = arma::unique(labels).eval();
  if (unq_.n_elem == 1)
    oneclass_ = true;
 
  unclass_ = unq_.n_elem;
  if (!oneclass_)
  {
    for(size_t i=0;i<unclass_;i++)
    {
      auto binlabels = arma::conv_to<arma::Row<size_t>>::from(labels==unq_(i));
      models_[i].Train(inputs, binlabels);
    }
  }
  else
    return;
}

Train() [2/2]

template<class MODEL , class T >

template<class... Args>

void algo::classification::OnevAll< MODEL, T >::Train	(	const arma::Mat< T > &	inputs,
		const arma::Row< size_t > &	labels,
		const Args &...	args
	)

Parameters

inputs	: X
labels	: y
args	: parameters for the model

Definition at line 72 of file multiclass_impl.h.

{ 
  if (!oneclass_)
  {
    models_.resize(unq_.n_elem);
    for(size_t i=0;i<unclass_;i++)
    {
      auto binlabels = arma::conv_to<arma::Row<size_t>>::from(labels==unq_(i));
      MODEL model(inputs,binlabels,args...);
      models_[i] = model;
    }
  }
} 

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The documentation for this class was generated from the following files:

• multiclass.h
• multiclass_impl.h