# Licensed under a 3-clause BSD style license - see LICENSE.rst import pytest import numpy as np from numpy.testing import assert_allclose, assert_array_equal, assert_array_less from astropy.modeling import models, InputParameterError from astropy.coordinates import Angle from astropy.modeling import fitting from astropy.tests.helper import catch_warnings from astropy.utils.exceptions import AstropyDeprecationWarning try: from scipy import optimize # pylint: disable=W0611 HAS_SCIPY = True except ImportError: HAS_SCIPY = False def test_sigma_constant(): """ Test that the GAUSSIAN_SIGMA_TO_FWHM constant matches the gaussian_sigma_to_fwhm constant in astropy.stats. We define it manually in astropy.modeling to avoid importing from astropy.stats. """ from astropy.stats.funcs import gaussian_sigma_to_fwhm from astropy.modeling.functional_models import GAUSSIAN_SIGMA_TO_FWHM assert gaussian_sigma_to_fwhm == GAUSSIAN_SIGMA_TO_FWHM def test_Trapezoid1D(): """Regression test for https://github.com/astropy/astropy/issues/1721""" model = models.Trapezoid1D(amplitude=4.2, x_0=2.0, width=1.0, slope=3) xx = np.linspace(0, 4, 8) yy = model(xx) yy_ref = [0., 1.41428571, 3.12857143, 4.2, 4.2, 3.12857143, 1.41428571, 0.] assert_allclose(yy, yy_ref, rtol=0, atol=1e-6) def test_Gaussian2D(): """ Test rotated elliptical Gaussian2D model. https://github.com/astropy/astropy/pull/2038 """ model = models.Gaussian2D(4.2, 1.7, 3.1, x_stddev=5.1, y_stddev=3.3, theta=np.pi/6.) y, x = np.mgrid[0:5, 0:5] g = model(x, y) g_ref = [[3.01907812, 2.99051889, 2.81271552, 2.5119566, 2.13012709], [3.55982239, 3.6086023, 3.4734158, 3.17454575, 2.75494838], [3.88059142, 4.0257528, 3.96554926, 3.70908389, 3.29410187], [3.91095768, 4.15212857, 4.18567526, 4.00652015, 3.64146544], [3.6440466, 3.95922417, 4.08454159, 4.00113878, 3.72161094]] assert_allclose(g, g_ref, rtol=0, atol=1e-6) assert_allclose([model.x_fwhm, model.y_fwhm], [12.009582229657841, 7.7709061486021325]) def test_Gaussian2DCovariance(): """ Test rotated elliptical Gaussian2D model when cov_matrix is input. https://github.com/astropy/astropy/pull/2199 """ cov_matrix = [[49., -16.], [-16., 9.]] model = models.Gaussian2D(17., 2.0, 2.5, cov_matrix=cov_matrix) y, x = np.mgrid[0:5, 0:5] g = model(x, y) g_ref = [[4.3744505, 5.8413977, 7.42988694, 9.00160175, 10.38794269], [8.83290201, 10.81772851, 12.61946384, 14.02225593, 14.84113227], [13.68528889, 15.37184621, 16.44637743, 16.76048705, 16.26953638], [16.26953638, 16.76048705, 16.44637743, 15.37184621, 13.68528889], [14.84113227, 14.02225593, 12.61946384, 10.81772851, 8.83290201]] assert_allclose(g, g_ref, rtol=0, atol=1e-6) def test_Gaussian2DRotation(): amplitude = 42 x_mean, y_mean = 0, 0 x_stddev, y_stddev = 2, 3 theta = Angle(10, 'deg') pars = dict(amplitude=amplitude, x_mean=x_mean, y_mean=y_mean, x_stddev=x_stddev, y_stddev=y_stddev) rotation = models.Rotation2D(angle=theta.degree) point1 = (x_mean + 2 * x_stddev, y_mean + 2 * y_stddev) point2 = rotation(*point1) g1 = models.Gaussian2D(theta=0, **pars) g2 = models.Gaussian2D(theta=theta.radian, **pars) value1 = g1(*point1) value2 = g2(*point2) assert_allclose(value1, value2) def test_Gaussian2D_invalid_inputs(): x_stddev = 5.1 y_stddev = 3.3 theta = 10 cov_matrix = [[49., -16.], [-16., 9.]] # first make sure the valid ones are OK models.Gaussian2D() models.Gaussian2D(x_stddev=x_stddev, y_stddev=y_stddev, theta=theta) models.Gaussian2D(x_stddev=None, y_stddev=y_stddev, theta=theta) models.Gaussian2D(x_stddev=x_stddev, y_stddev=None, theta=theta) models.Gaussian2D(x_stddev=x_stddev, y_stddev=y_stddev, theta=None) models.Gaussian2D(cov_matrix=cov_matrix) with pytest.raises(InputParameterError): models.Gaussian2D(x_stddev=0, cov_matrix=cov_matrix) with pytest.raises(InputParameterError): models.Gaussian2D(y_stddev=0, cov_matrix=cov_matrix) with pytest.raises(InputParameterError): models.Gaussian2D(theta=0, cov_matrix=cov_matrix) @pytest.mark.parametrize('gamma', (10, -10)) def test_moffat_fwhm(gamma): ans = 34.641016151377542 kwargs = {'gamma': gamma, 'alpha': 0.5} m1 = models.Moffat1D(**kwargs) m2 = models.Moffat2D(**kwargs) assert_allclose([m1.fwhm, m2.fwhm], ans) assert_array_less(0, [m1.fwhm, m2.fwhm]) def test_RedshiftScaleFactor(): """Like ``test_ScaleModel()``.""" # Scale by a scalar m = models.RedshiftScaleFactor(0.4) assert m(0) == 0 assert_array_equal(m([1, 2]), [1.4, 2.8]) assert_allclose(m.inverse(m([1, 2])), [1, 2]) # Scale by a list m = models.RedshiftScaleFactor([-0.5, 0, 0.5], n_models=3) assert_array_equal(m(0), 0) assert_array_equal(m([1, 2], model_set_axis=False), [[0.5, 1], [1, 2], [1.5, 3]]) assert_allclose(m.inverse(m([1, 2], model_set_axis=False)), [[1, 2], [1, 2], [1, 2]]) def test_Ellipse2D(): """Test Ellipse2D model.""" amplitude = 7.5 x0, y0 = 15, 15 theta = Angle(45, 'deg') em = models.Ellipse2D(amplitude, x0, y0, 7, 3, theta.radian) y, x = np.mgrid[0:30, 0:30] e = em(x, y) assert np.all(e[e > 0] == amplitude) assert e[y0, x0] == amplitude rotation = models.Rotation2D(angle=theta.degree) point1 = [2, 0] # Rotation2D center is (0, 0) point2 = rotation(*point1) point1 = np.array(point1) + [x0, y0] point2 = np.array(point2) + [x0, y0] e1 = models.Ellipse2D(amplitude, x0, y0, 7, 3, theta=0.) e2 = models.Ellipse2D(amplitude, x0, y0, 7, 3, theta=theta.radian) assert e1(*point1) == e2(*point2) def test_Ellipse2D_circular(): """Test that circular Ellipse2D agrees with Disk2D [3736].""" amplitude = 7.5 radius = 10 size = (radius * 2) + 1 y, x = np.mgrid[0:size, 0:size] ellipse = models.Ellipse2D(amplitude, radius, radius, radius, radius, theta=0)(x, y) disk = models.Disk2D(amplitude, radius, radius, radius)(x, y) assert np.all(ellipse == disk) def test_Scale_inverse(): m = models.Scale(1.2345) assert_allclose(m.inverse(m(6.789)), 6.789) def test_Multiply_inverse(): m = models.Multiply(1.2345) assert_allclose(m.inverse(m(6.789)), 6.789) def test_Shift_inverse(): m = models.Shift(1.2345) assert_allclose(m.inverse(m(6.789)), 6.789) @pytest.mark.skipif('not HAS_SCIPY') def test_Shift_model_levmar_fit(): """Test fitting Shift model with LevMarLSQFitter (issue #6103).""" init_model = models.Shift() x = np.arange(10) y = x+0.1 fitter = fitting.LevMarLSQFitter() fitted_model = fitter(init_model, x, y) assert_allclose(fitted_model.parameters, [0.1], atol=1e-15) def test_Shift_model_set_linear_fit(): """Test linear fitting of Shift model (issue #6103).""" init_model = models.Shift(offset=[0, 0], n_models=2) x = np.arange(10) yy = np.array([x+0.1, x-0.2]) fitter = fitting.LinearLSQFitter() fitted_model = fitter(init_model, x, yy) assert_allclose(fitted_model.parameters, [0.1, -0.2], atol=1e-15) @pytest.mark.parametrize('Model', (models.Scale, models.Multiply)) def test_Scale_model_set_linear_fit(Model): """Test linear fitting of Scale model (#6103).""" init_model = Model(factor=[0, 0], n_models=2) x = np.arange(-3, 7) yy = np.array([1.15*x, 0.96*x]) fitter = fitting.LinearLSQFitter() fitted_model = fitter(init_model, x, yy) assert_allclose(fitted_model.parameters, [1.15, 0.96], atol=1e-15) # https://github.com/astropy/astropy/issues/6178 def test_Ring2D_rout(): m = models.Ring2D(amplitude=1, x_0=1, y_0=1, r_in=2, r_out=5) assert m.width.value == 3 @pytest.mark.skipif("not HAS_SCIPY") def test_Voigt1D(): voi = models.Voigt1D(amplitude_L=-0.5, x_0=1.0, fwhm_L=5.0, fwhm_G=5.0) xarr = np.linspace(-5.0, 5.0, num=40) yarr = voi(xarr) voi_init = models.Voigt1D(amplitude_L=-1.0, x_0=1.0, fwhm_L=5.0, fwhm_G=5.0) fitter = fitting.LevMarLSQFitter() voi_fit = fitter(voi_init, xarr, yarr) assert_allclose(voi_fit.param_sets, voi.param_sets) @pytest.mark.skipif("not HAS_SCIPY") def test_compound_models_with_class_variables(): models_2d = [models.AiryDisk2D, models.Sersic2D] models_1d = [models.Sersic1D] for model_2d in models_2d: class CompoundModel2D(models.Const2D + model_2d): pass x, y = np.mgrid[:10, :10] f = CompoundModel2D()(x, y) assert f.shape == (10, 10) for model_1d in models_1d: class CompoundModel1D(models.Const1D + model_1d): pass x = np.arange(10) f = CompoundModel1D()(x) assert f.shape == (10,)