Class: VectorModel

Inherits:
Object
  • Object
show all
Defined in:
lib/rbbt/vector/model.rb

Direct Known Subclasses

SVMModel

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(directory, extract_features = nil, train_model = nil, eval_model = nil) ⇒ VectorModel

Returns a new instance of VectorModel.



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# File 'lib/rbbt/vector/model.rb', line 49

def initialize(directory, extract_features = nil, train_model = nil, eval_model = nil)
  @directory = directory
  FileUtils.mkdir_p @directory unless File.exists? @directory
  @model_file = File.join(@directory, "model")
  extract_features = @extract_features 
  train_model = @train_model 
  eval_model = @eval_model
  @features = []
  @labels = []
end

Instance Attribute Details

#directoryObject

Returns the value of attribute directory.



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# File 'lib/rbbt/vector/model.rb', line 4

def directory
  @directory
end

#eval_modelObject

Returns the value of attribute eval_model.



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# File 'lib/rbbt/vector/model.rb', line 4

def eval_model
  @eval_model
end

#extract_featuresObject

Returns the value of attribute extract_features.



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# File 'lib/rbbt/vector/model.rb', line 4

def extract_features
  @extract_features
end

#featuresObject

Returns the value of attribute features.



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# File 'lib/rbbt/vector/model.rb', line 5

def features
  @features
end

#labelsObject

Returns the value of attribute labels.



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# File 'lib/rbbt/vector/model.rb', line 5

def labels
  @labels
end

#model_fileObject

Returns the value of attribute model_file.



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# File 'lib/rbbt/vector/model.rb', line 4

def model_file
  @model_file
end

#train_modelObject

Returns the value of attribute train_model.



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# File 'lib/rbbt/vector/model.rb', line 4

def train_model
  @train_model
end

Class Method Details

.R_eval(model_file, features, list, code) ⇒ Object



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# File 'lib/rbbt/vector/model.rb', line 22

def self.R_eval(model_file, features, list, code)
  TmpFile.with_file do |feature_file|
    TmpFile.with_file do |results|
      if list
        Open.write(feature_file, features.collect{|feat| feat * "\t"} * "\n" + "\n")
      else
        Open.write(feature_file, features * "\t" + "\n")
      end

      io = R.run <<-EOF
features = read.table("#{ feature_file }", sep ="\\t", stringsAsFactors=FALSE);
load(file="#{model_file}");
#{code}
cat(paste(label, sep="\\n"));
      EOF

      res = io.read.sub(/WARNING: .*?\n/s,'').split(/\s+/).collect{|l| l.to_f}

      if list
        res
      else
        res.first
      end
    end
  end
end

.R_train(model_file, features, labels, code) ⇒ Object



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# File 'lib/rbbt/vector/model.rb', line 7

def self.R_train(model_file, features, labels, code)
  TmpFile.with_file do |feature_file|
    Open.write(feature_file, features.collect{|feats| feats * "\t"} * "\n")
    Open.write(feature_file + '.class', labels * "\n")

    R.run <<-EOF
features = read.table("#{ feature_file }", sep ="\\t", stringsAsFactors=FALSE);
labels = scan("#{ feature_file }.class");
features = cbind(features, class = labels);
#{code}
save(model, file='#{model_file}')
    EOF
  end
end

Instance Method Details

#add(element, label = nil) ⇒ Object



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# File 'lib/rbbt/vector/model.rb', line 60

def add(element, label = nil)
  @features << extract_features.call(element)
  @labels << label unless label.nil?
end

#cross_validation(folds = 10) ⇒ Object



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# File 'lib/rbbt/vector/model.rb', line 92

def cross_validation(folds = 10)
  saved_features = @features
  saved_labels = @labels
  seq = (0..features.length - 1).to_a

  chunk_size = features.length / folds

  acc = []
  folds.times do
    seq = seq.shuffle
    eval_chunk = seq[0..chunk_size]
    train_chunk = seq[chunk_size.. -1]

    eval_features = @features.values_at *eval_chunk
    eval_labels = @labels.values_at *eval_chunk

    @features = @features.values_at *train_chunk
    @labels = @labels.values_at *train_chunk

    train
    predictions = eval_list eval_features, false

    acc << predictions.zip(eval_labels).collect{|pred,lab| pred - lab < 0.5 ? 1 : 0}.inject(0){|acc,e| acc +=e} / chunk_size

    @features = saved_features
    @labels = saved_labels
  end

  acc
end

#eval(element) ⇒ Object



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# File 'lib/rbbt/vector/model.rb', line 74

def eval(element)
  case 
  when Proc === eval_model
    eval_model.call(@model_file, extract_features.call(element), false)
  when String === eval_model
    SVMModel.R_eval(@model_file,  extract_features.call(element), false, eval_model)
  end
end

#eval_list(elements, extract = true) ⇒ Object



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# File 'lib/rbbt/vector/model.rb', line 83

def eval_list(elements, extract = true)
  case 
  when Proc === eval_model
    eval_model.call(@model_file, extract ? elements.collect{|element| extract_features.call(element)} : elements, true)
  when String === eval_model
    SVMModel.R_eval(@model_file, extract ? elements.collect{|element| extract_features.call(element)} : elements, true, eval_model)
  end
end

#trainObject



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# File 'lib/rbbt/vector/model.rb', line 65

def train
  case 
  when Proc === train_model
    train_model.call(@model_file, @features, @labels)
  when String === train_model
    SVMModel.R_train(@model_file,  @features, @labels, train_model)
  end
end