def test_success(): f.calls = 0 result = rootfinding.bracket_root(f, (0, -0.1)) check_result(result, f, f_calls=f.calls, has_bracket=True, has_root=False) assert result.iterations >= 1 rootfinding.bisect(f, result.bracket, f_bracket=result.f_bracket)
def test_growth_factor2(): growth_factor = 3.14 interval = (0, -0.1) f.calls = 0 result = rootfinding.bracket_root(f, interval, growth_factor=growth_factor) check_result(result, f, f_calls=f.calls, has_bracket=True, has_root=False) assert result.bracket[1] - result.bracket[0] == pytest.approx( (interval[1] - interval[0]) * growth_factor**result.iterations)
def test_iterationlimit(): f.calls = 0 with pytest.raises(rootfinding.IterationLimitReached) as exc_info: result = rootfinding.bracket_root(f, (-1, -2)) exc = exc_info.value check_iterationlimitreached(exc, f, f_calls=f.calls) with pytest.raises(rootfinding.NotABracketError): rootfinding.bisect(f, exc.interval, f_bracket=exc.f_interval)
def test_instantbracket(): interval = (0, 2) f_interval = (None, f(interval[1])) f.calls = 0 result = rootfinding.bracket_root(f, interval, f_interval=f_interval, maxiter=0) assert f.calls == 1 check_result(result, f, f_calls=f.calls, has_bracket=True, has_root=False) rootfinding.bisect(f, result.bracket, f_bracket=result.f_bracket)
def test_instantroot2(): interval = (-1, 0) f_interval = (f(interval[0]), None) ftol = 0 f.calls = 0 result = rootfinding.bracket_root(f, interval, f_interval=f_interval, ftol=ftol, maxiter=0) assert f.calls == 1 check_result(result, f, ftol=ftol, f_calls=f.calls, has_bracket=False, has_root=True)
def test_instantrootwithbracket(): interval = (0, -1.00001) f_interval = (f(interval[0]), None) ftol = 1e-3 f.calls = 0 result = rootfinding.bracket_root(f, interval, f_interval=f_interval, ftol=ftol, maxiter=0) assert f.calls == 1 check_result(result, f, ftol=ftol, f_calls=f.calls, has_bracket=True, has_root=True) rootfinding.bisect(f, result.bracket)
def test_invalidmaxiter(): with pytest.raises(ValueError): rootfinding.bracket_root(f, (0, -0.1), maxiter=-0.5)
def test_invalidftol(): with pytest.raises(ValueError): rootfinding.bracket_root(f, (0, -0.1), ftol=-1e-3)
def test_invalidgrowth_factor(): with pytest.raises(ValueError): rootfinding.bracket_root(f, (0, -0.1), growth_factor=0.5)
def test_invalidinterval(): with pytest.raises(ValueError): rootfinding.bracket_root(f, (0, 0))