test_pearson_1d.py

"""
Test Pearson module, pearson_1d function

Run with::

    python3 -m pytest test_pearson_1d.py

This is a test module.

It is designed to be run the with the "pytest" testing package (via the
"pytest" script above).

Pytest will look for any functions with "test" in their names, and run them.
pytest reports any errors, or any failures.

A failure is where one of the test conditions run with an "assert" command
fails.  For example, if I did:

    assert_almost_equal(1, 2)

then this would "fail".

So we use the tests to check that the results of our function are (still) as we
expect.
"""

import numpy as np

import pearson


def test_pearson_1d():
    # Test pearson_1d routine
    x = np.random.rand(22)
    y = np.random.rand(22)
    # Does routine give same answer as np.corrcoef?
    expected = np.corrcoef(x, y)[0, 1]
    actual = pearson.pearson_1d(x, y)
    # Did you, gentle user, forget to return the value?
    if actual is None:
        raise RuntimeError("function returned None")
    assert np.allclose(expected, actual)