require 'test_helper'

class MatrixNmfTest < GSL::TestCase

  def setup
    @m1 = GSL::Matrix.alloc([6, 7, 8], [2, 3, 4], [3, 4, 5])
    @m2 = GSL::Matrix.alloc([6, 7, 8], [2, 3, 4], [3, 4, 7])
  end

  def test_difcost
    assert_equal 0, GSL::Matrix::NMF.difcost(@m1, @m1)
    assert_equal 4, GSL::Matrix::NMF.difcost(@m1, @m2)
  end

  def test_nmf
    [2, 3, 4, 5].each { |cols|
      res = GSL::Matrix::NMF.nmf(@m1, cols)
      assert_equal [3, cols], res[0].size
      assert_equal [cols, 3], res[1].size

      cost = GSL::Matrix::NMF.difcost(@m1, res[0] * res[1])
      assert cost <= 0.0001, "Cols: #{cols}, Delta: #{cost}"
    }
  end

  def test_matrix_nmf
    [2, 3, 4, 5].each { |cols|
      res = @m1.nmf(cols)
      assert_equal [3, cols], res[0].size
      assert_equal [cols, 3], res[1].size

      cost = GSL::Matrix::NMF.difcost(@m1, res[0] * res[1])
      assert cost <= 0.0001, "Cols: #{cols}, Delta: #{cost}"
    }
  end

end