# imports
import numpy as np
import unittest

# objects to test
from bsfs.triple_store.sparql import distance


## code ##

class TestDistance(unittest.TestCase):

    def test_euclid(self):
        # self-distance is zero
        self.assertEqual(distance.euclid([1,2,3,4], [1,2,3,4]), 0.0)
        # accepts list-like arguments
        self.assertAlmostEqual(distance.euclid([1,2,3,4], [2,3,4,5]), 2.0, 3)
        self.assertAlmostEqual(distance.euclid((1,2,3,4), (2,3,4,5)), 2.0, 3)
        # dimension can vary
        self.assertAlmostEqual(distance.euclid([1,2,3], [2,3,4]), 1.732, 3)
        self.assertAlmostEqual(distance.euclid([1,2,3,4,5], [2,3,4,5,6]), 2.236, 3)
        # vector can be zero
        self.assertAlmostEqual(distance.euclid([0,0,0], [1,2,3]), 3.742, 3)

    def test_cosine(self):
        # self-distance is zero
        self.assertEqual(distance.cosine([1,2,3,4], [1,2,3,4]), 0.0)
        # accepts list-like arguments
        self.assertAlmostEqual(distance.cosine([1,2,3,4], [4,3,2,1]), 0.333, 3)
        self.assertAlmostEqual(distance.cosine((1,2,3,4), (4,3,2,1)), 0.333, 3)
        # dimension can vary
        self.assertAlmostEqual(distance.cosine([1,2,3], [3,2,1]), 0.286, 3)
        self.assertAlmostEqual(distance.cosine([1,2,3,4,5], [5,4,3,2,1]), 0.364, 3)
        # vector can be zero
        self.assertAlmostEqual(distance.cosine([0,0,0], [1,2,3]), 1.0, 3)

    def test_manhatten(self):
        # self-distance is zero
        self.assertEqual(distance.manhatten([1,2,3,4], [1,2,3,4]), 0.0)
        # accepts list-like arguments
        self.assertAlmostEqual(distance.manhatten([1,2,3,4], [2,3,4,5]), 4.0, 3)
        self.assertAlmostEqual(distance.manhatten((1,2,3,4), (2,3,4,5)), 4.0, 3)
        # dimension can vary
        self.assertAlmostEqual(distance.manhatten([1,2,3], [2,3,4]), 3.0, 3)
        self.assertAlmostEqual(distance.manhatten([1,2,3,4,5], [2,3,4,5,6]), 5.0, 3)
        # vector can be zero
        self.assertAlmostEqual(distance.manhatten([0,0,0], [1,2,3]), 6.0, 3)


## main ##

if __name__ == '__main__':
    unittest.main()

## EOF ##