Method: Matrix#random_forest_importance

Defined in:
lib/rbbt/expression_old/matrix.rb

#random_forest_importance(main, contrast = nil, field = nil, options = {}) ⇒ Object



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# File 'lib/rbbt/expression_old/matrix.rb', line 125

def random_forest_importance(main, contrast = nil, field = nil, options = {})
  features = Misc.process_options options, :features
  features ||= []

  path = Persist.persistence_path(matrix_file, {:dir => File.join(Matrix::MATRIX_DIR, 'random_forest_importance')}, {:main => main, :contrast => contrast, :field => field, :features => features})
  Persist.persist(data, :tsv, :file => path, :no_load => false, :check => [matrix_file]) do
    all_samples = labels.keys
    main_samples = find_samples(main, field)
    if contrast
      contrast_samples = find_samples(contrast, field)
    else
      contrast_samples = all_samples - main_samples
    end


    main_samples     = remove_missing(main_samples)
    contrast_samples = remove_missing(contrast_samples)

    TmpFile.with_file do |result|
      R.run <<-EOF
library(randomForest);
orig = rbbt.tsv('#{matrix_file}');
main = c('#{main_samples * "', '"}')
contrast = c('#{contrast_samples * "', '"}')
features = c('#{features * "', '"}')

features = intersect(features, rownames(orig));
data = t(orig[features, c(main, contrast)])
data = cbind(data, Class = 0)
data[main, "Class"] = 1

rf = randomForest(factor(Class) ~ ., data, na.action = na.exclude)
rbbt.tsv.write(rf$importance, filename='#{ result }', key.field = '#{@key_field}')
      EOF

      TSV.open(result, :type => :single, :cast => :to_f)
    end
  end
end