[test] add meltohz tests

diff --git a/python/tests/test_meltohz.py b/python/tests/test_meltohz.py
new file mode 100755 (executable)
index 0000000..165f2ee
--- /dev/null
+++ b/python/tests/test_meltohz.py
@@ -0,0 +1,109 @@
+#! /usr/bin/env python
+
+from unittest import main
+from numpy.testing import TestCase
+from numpy.testing import assert_equal, assert_almost_equal
+import numpy as np
+import aubio
+
+from aubio import hztomel, meltohz
+from aubio import hztomel_htk, meltohz_htk
+
+
+class aubio_hztomel_test_case(TestCase):
+
+    def test_hztomel(self):
+        assert_equal(hztomel(0.), 0.)
+        assert_almost_equal(hztomel(400. / 3.), 2., decimal=5)
+        assert_equal(hztomel(1000. / 3), 5.)
+        assert_equal(hztomel(200.), 3.)
+        assert_almost_equal(hztomel(1000.), 15)
+        assert_almost_equal(hztomel(6400), 42)
+        assert_almost_equal(hztomel(40960), 69)
+
+        for m in np.linspace(0, 1000, 100):
+            assert_almost_equal(hztomel(meltohz(m)) - m, 0, decimal=3)
+
+    def test_meltohz(self):
+        assert_equal(meltohz(0.), 0.)
+        assert_almost_equal(meltohz(2), 400. / 3., decimal=4)
+        assert_equal(meltohz(3.), 200.)
+        assert_almost_equal(meltohz(5), 1000. / 3., decimal=4)
+        assert_almost_equal(meltohz(15), 1000., decimal=4)
+        assert_almost_equal(meltohz(42), 6400., decimal=2)
+        assert_almost_equal(meltohz(69), 40960., decimal=1)
+
+        for f in np.linspace(0, 20000, 1000):
+            assert_almost_equal(meltohz(hztomel(f)) - f, 0, decimal=1)
+
+    def test_meltohz_negative(self):
+        # TODO add assert_warns
+        assert_equal(meltohz(-1), 0)
+
+    def test_hztomel_negative(self):
+        # TODO add assert_warns
+        assert_equal(hztomel(-1), 0)
+
+
+class aubio_hztomel_htk_test_case(TestCase):
+
+    def test_meltohz(self):
+        assert_equal(meltohz(0, htk=True), 0)
+        assert_almost_equal(meltohz(2595, htk=True), 6300., decimal=1)
+
+    def test_hztomel(self):
+        assert_equal(hztomel(0, htk=True), 0)
+        assert_almost_equal(hztomel(3428.7, htk=True), 2000., decimal=1)
+        assert_almost_equal(hztomel(6300, htk=True), 2595., decimal=1)
+
+    def test_meltohz_negative(self):
+        # TODO add assert_warns
+        assert_equal(meltohz(-1, htk=True), 0)
+        assert_almost_equal(meltohz(2000, htk=True), 3428.7, decimal=1)
+        assert_almost_equal(meltohz(1000, htk=True), 1000., decimal=1)
+
+    def test_hztomel_negative(self):
+        # TODO add assert_warns
+        assert_equal(hztomel(-1, htk=True), 0)
+        assert_almost_equal(hztomel(1000, htk=True), 1000., decimal=1)
+
+    def test_hztomel_htk(self):
+        for f in np.linspace(0, 20000, 1000):
+            assert_almost_equal(meltohz_htk(hztomel_htk(f)) - f, 0, decimal=1)
+        for f in np.linspace(0, 20000, 1000):
+            assert_almost_equal(hztomel_htk(meltohz_htk(f)) - f, 0, decimal=1)
+
+
+class aubio_hztomel_wrong_values(TestCase):
+    """ more tests to cover all branches """
+
+    def test_hztomel_wrong_values(self):
+        with self.assertRaises(TypeError):
+            hztomel('s')
+
+    def test_meltohz_wrong_values(self):
+        with self.assertRaises(TypeError):
+            meltohz(bytes('ad'))
+
+    def test_meltohz_no_arg(self):
+        with self.assertRaises(TypeError):
+            meltohz()
+
+    def test_meltohz_htk_no_arg(self):
+        with self.assertRaises(TypeError):
+            meltohz_htk()
+
+    def test_hztomel_htk_wrong_values(self):
+        with self.assertRaises(TypeError):
+            hztomel_htk('0')
+
+    def test_hztomel_htk_false(self):
+        assert hztomel(120, htk=False) == hztomel(120)
+
+    def test_meltohz_htk_false(self):
+        assert meltohz(12, htk=False) == meltohz(12)
+
+
+if __name__ == '__main__':
+    from unittest import main
+    main()