calculations_test.py

import math
import unittest

import calculations


class TestCalculations(unittest.TestCase):
    def test_calculate_slot_angles(self):
        # From page 4 of
        # https://www.heldermann-verlag.de/jgg/jgg15/j15h1mone.pdf
        expected_angles = [76.9, 63.4, 49.1, 33.7, 17.2, 0, -17.2, -33.7,
                           -49.1, -63.4, -76.9]
        actual_angles = [
            math.degrees(r)
            for r in calculations.slot_angles(12, math.pi / 6)]

        self.assertEqual(len(actual_angles), len(expected_angles))

        for actual, expected in zip(actual_angles, expected_angles):
            self.assertAlmostEqual(actual, expected, places=1)

    def test_slot_width(self):
        for material_thickness in range(10):
            actual_width = calculations.slot_width(material_thickness,
                                                   math.radians(90))
            self.assertAlmostEqual(actual_width, material_thickness)

            actual_width = calculations.slot_width(material_thickness,
                                                   math.radians(45))
            self.assertAlmostEqual(
                actual_width,
                material_thickness + math.sqrt(2) * material_thickness)

            actual_width = calculations.slot_width(material_thickness,
                                                   math.radians(180 - 45))
            self.assertAlmostEqual(
                actual_width,
                material_thickness + math.sqrt(2) * material_thickness)

            actual_width = calculations.slot_width(material_thickness,
                                                   math.radians(60))
            self.assertAlmostEqual(
                actual_width,
                3 * material_thickness / math.sqrt(3))

            actual_width = calculations.slot_width(material_thickness,
                                                   math.radians(180 - 60))
            self.assertAlmostEqual(
                actual_width,
                3 * material_thickness / math.sqrt(3))


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