"""ctrlutil_test.py"""

import numpy as np

import pytest

import control as ct

from control.ctrlutil import db2mag, mag2db, unwrap

class TestUtils:

mag = np.array([1, 10, 100, 2, 0.1, 0.01])

db = np.array([0, 20, 40, 6.0205999, -20, -40])

def check_unwrap_array(self, angle, period=None):

if period is None:

angle_mod = angle % (2 * np.pi)

angle_unwrap = unwrap(angle_mod)

else:

angle_mod = angle % period

angle_unwrap = unwrap(angle_mod, period)

np.testing.assert_array_almost_equal(angle_unwrap, angle)

def test_unwrap_increasing(self):

angle = np.linspace(0, 20, 50)

self.check_unwrap_array(angle)

def test_unwrap_decreasing(self):

angle = np.linspace(0, -20, 50)

self.check_unwrap_array(angle)

def test_unwrap_inc_degrees(self):

angle = np.linspace(0, 720, 50)

self.check_unwrap_array(angle, 360)

def test_unwrap_dec_degrees(self):

angle = np.linspace(0, -720, 50)

self.check_unwrap_array(angle, 360)

def test_unwrap_large_skips(self):

angle = np.array([0., 4 * np.pi, -2 * np.pi])

np.testing.assert_array_almost_equal(unwrap(angle), [0., 0., 0.])

def test_unwrap_list(self):

angle = [0, 2.2, 5.4, -0.4]

angle_unwrapped = [0, 0.2, 0.4, 0.6]

np.testing.assert_array_almost_equal(unwrap(angle, 1.0), angle_unwrapped)

def test_db2mag(self):

for mag, db in zip(self.mag, self.db):

np.testing.assert_almost_equal(mag, db2mag(db))

def test_db2mag_array(self):

mag_array = db2mag(self.db)

np.testing.assert_array_almost_equal(mag_array, self.mag)

def test_mag2db(self):

for db, mag in zip(self.db, self.mag):

np.testing.assert_almost_equal(db, mag2db(mag))

def test_mag2db_array(self):

db_array = mag2db(self.mag)

np.testing.assert_array_almost_equal(db_array, self.db)

def test_issys(self):

sys = ct.rss(2, 1, 1)

with pytest.warns(FutureWarning, match="deprecated; use isinstance"):

ct.issys(sys)