math_isclose.py

# test math.isclose (appeared in Python 3.5)

try:
    from math import isclose
except ImportError:
    print("SKIP")
    raise SystemExit


def test(a, b, **kwargs):
    print(isclose(a, b, **kwargs))


def test_combinations(a, b, **kwargs):
    test(a, a, **kwargs)
    test(a, b, **kwargs)
    test(b, a, **kwargs)
    test(b, b, **kwargs)


# Special numbers
test_combinations(float("nan"), 1)
test_combinations(float("inf"), 1)
test_combinations(float("-inf"), 1)

# Equality
test(1.0, 1.0, rel_tol=0.0, abs_tol=0.0)
test(2.35e-100, 2.35e-100, rel_tol=0.0, abs_tol=0.0)
test(2.1234e100, 2.1234e100, rel_tol=0.0, abs_tol=0.0)

# Relative tolerance
test(1000.0, 1001.0, rel_tol=1e-3)
test(1000.0, 1001.0, rel_tol=1e-4)
test(1000, 1001, rel_tol=1e-3)
test(1000, 1001, rel_tol=1e-4)
test_combinations(0, 1, rel_tol=1.0)

# Absolute tolerance
test(0.0, 1e-10, abs_tol=1e-10, rel_tol=0.1)
test(0.0, 1e-10, abs_tol=0.0, rel_tol=0.1)

# Bad parameters
try:
    isclose(0, 0, abs_tol=-1)
except ValueError:
    print("ValueError")
try:
    isclose(0, 0, rel_tol=-1)
except ValueError:
    print("ValueError")