Example #1
0
class TestEPLvsNIE(object):
    """
    tests the Gaussian methods
    """
    def setup(self):
        from lenstronomy.LensModel.Profiles.epl import EPL
        self.EPL = EPL()
        from lenstronomy.LensModel.Profiles.nie import NIE
        self.NIE = NIE()

    def test_function(self):
        phi_E = 1.
        gamma = 2.
        q = 0.999
        phi_G = 1.
        e1, e2 = param_util.phi_q2_ellipticity(phi_G, q)
        x = np.array([1., 2])
        y = np.array([2, 0])
        values = self.EPL.function(x, y, phi_E, gamma, e1, e2)
        values_nie = self.NIE.function(x, y, phi_E, e1, e2, 0.)
        delta_f = values[0] - values[1]
        delta_f_nie = values_nie[0] - values_nie[1]
        npt.assert_almost_equal(delta_f, delta_f_nie, decimal=5)

        q = 0.8
        e1, e2 = param_util.phi_q2_ellipticity(phi_G, q)
        x = np.array([1., 2])
        y = np.array([2, 0])
        values = self.EPL.function(x, y, phi_E, gamma, e1, e2)
        values_nie = self.NIE.function(x, y, phi_E, e1, e2, 0.)
        delta_f = values[0] - values[1]
        delta_f_nie = values_nie[0] - values_nie[1]
        npt.assert_almost_equal(delta_f, delta_f_nie, decimal=5)

        q = 0.4
        e1, e2 = param_util.phi_q2_ellipticity(phi_G, q)
        x = np.array([1., 2])
        y = np.array([2, 0])
        values = self.EPL.function(x, y, phi_E, gamma, e1, e2)
        values_nie = self.NIE.function(x, y, phi_E, e1, e2, 0.)
        delta_f = values[0] - values[1]
        delta_f_nie = values_nie[0] - values_nie[1]
        npt.assert_almost_equal(delta_f, delta_f_nie, decimal=5)

    def test_derivatives(self):
        x = np.array([1])
        y = np.array([2])
        phi_E = 1.
        gamma = 2.
        q = 1.
        phi_G = 1.
        e1, e2 = param_util.phi_q2_ellipticity(phi_G, q)
        f_x, f_y = self.EPL.derivatives(x, y, phi_E, gamma, e1, e2)
        f_x_nie, f_y_nie = self.NIE.derivatives(x, y, phi_E, e1, e2, 0.)
        npt.assert_almost_equal(f_x, f_x_nie, decimal=4)
        npt.assert_almost_equal(f_y, f_y_nie, decimal=4)

        q = 0.7
        phi_G = 1.
        e1, e2 = param_util.phi_q2_ellipticity(phi_G, q)
        f_x, f_y = self.EPL.derivatives(x, y, phi_E, gamma, e1, e2)
        f_x_nie, f_y_nie = self.NIE.derivatives(x, y, phi_E, e1, e2, 0.)
        npt.assert_almost_equal(f_x, f_x_nie, decimal=4)
        npt.assert_almost_equal(f_y, f_y_nie, decimal=4)

    def test_hessian(self):
        x = np.array([1.])
        y = np.array([2.])
        phi_E = 1.
        gamma = 2.
        q = 0.9
        phi_G = 1.
        e1, e2 = param_util.phi_q2_ellipticity(phi_G, q)
        f_xx, f_xy, f_yx, f_yy = self.EPL.hessian(x, y, phi_E, gamma, e1, e2)
        f_xx_nie, f_xy_nie, f_yx_nie, f_yy_nie = self.NIE.hessian(x, y, phi_E, e1, e2, 0.)
        npt.assert_almost_equal(f_xx, f_xx_nie, decimal=4)
        npt.assert_almost_equal(f_yy, f_yy_nie, decimal=4)
        npt.assert_almost_equal(f_xy, f_xy_nie, decimal=4)
        npt.assert_almost_equal(f_xy, f_yx, decimal=8)

    def test_density_lens(self):
        r = 1
        kwargs = {'theta_E': 1, 'gamma': 2, 'e1': 0, 'e2': 0}
        rho = self.EPL.density_lens(r, **kwargs)
        from lenstronomy.LensModel.Profiles.spep import SPEP
        spep = SPEP()
        rho_spep = spep.density_lens(r, **kwargs)
        npt.assert_almost_equal(rho, rho_spep, decimal=7)

    def test_mass_3d_lens(self):
        r = 1
        kwargs = {'theta_E': 1, 'gamma': 2, 'e1': 0, 'e2': 0}
        rho = self.EPL.mass_3d_lens(r, **kwargs)
        from lenstronomy.LensModel.Profiles.spep import SPEP
        spep = SPEP()
        rho_spep = spep.mass_3d_lens(r, **kwargs)
        npt.assert_almost_equal(rho, rho_spep, decimal=7)

    def test_static(self):
        x, y = 1., 1.
        phi_G, q = 0.3, 0.8
        e1, e2 = param_util.phi_q2_ellipticity(phi_G, q)
        kwargs_lens = {'theta_E': 1., 'gamma': 1.5, 'e1': e1, 'e2': e2}
        f_ = self.EPL.function(x, y, **kwargs_lens)
        self.EPL.set_static(**kwargs_lens)
        f_static = self.EPL.function(x, y, **kwargs_lens)
        npt.assert_almost_equal(f_, f_static, decimal=8)
        self.EPL.set_dynamic()
        kwargs_lens = {'theta_E': 2., 'gamma': 1.9, 'e1': e1, 'e2': e2}
        f_dyn = self.EPL.function(x, y, **kwargs_lens)
        assert f_dyn != f_static

    def test_regularization(self):

        phi_E = 1.
        gamma = 2.
        q = 1.
        phi_G = 1.
        e1, e2 = param_util.phi_q2_ellipticity(phi_G, q)

        x = 0.
        y = 0.
        f_x, f_y = self.EPL.derivatives(x, y, phi_E, gamma, e1, e2)
        npt.assert_almost_equal(f_x, 0.)
        npt.assert_almost_equal(f_y, 0.)

        x = 0.
        y = 0.
        f_xx, f_xy, f_yx, f_yy = self.EPL.hessian(x, y, phi_E, gamma, e1, e2)
        assert f_xx > 10 ** 5
        assert f_yy > 10 ** 5
        #npt.assert_almost_equal(f_xx, 10**10)
        #npt.assert_almost_equal(f_yy, 10**10)
        npt.assert_almost_equal(f_xy, 0)
        npt.assert_almost_equal(f_yx, 0)
Example #2
0
class SIE(LensProfileBase):
    """
    class for singular isothermal ellipsoid (SIS with ellipticity)

    .. math::
        \\kappa(x, y) = \\frac{1}{2} \\left(\\frac{\\theta_{E}}{\\sqrt{q x^2 + y^2/q}} \\right)

    with :math:`\\theta_{E}` is the (circularized) Einstein radius,
    :math:`q` is the minor/major axis ratio,
    and :math:`x` and :math:`y` are defined in a coordinate sys- tem aligned with the major and minor axis of the lens.

    In terms of eccentricities, this profile is defined as

    .. math::
        \\kappa(r) = \\frac{1}{2} \\left(\\frac{\\theta'_{E}}{r \\sqrt{1 − e*\\cos(2*\\phi)}} \\right)

    with :math:`\\epsilon` is the ellipticity defined as

    .. math::
        \\epsilon = \\frac{1-q^2}{1+q^2}

    And an Einstein radius :math:`\\theta'_{\\rm E}` related to the definition used is

    .. math::
        \\left(\\frac{\\theta'_{\\rm E}}{\\theta_{\\rm E}}\\right)^{2} = \\frac{2q}{1+q^2}.

    """
    param_names = ['theta_E', 'e1', 'e2', 'center_x', 'center_y']
    lower_limit_default = {
        'theta_E': 0,
        'e1': -0.5,
        'e2': -0.5,
        'center_x': -100,
        'center_y': -100
    }
    upper_limit_default = {
        'theta_E': 100,
        'e1': 0.5,
        'e2': 0.5,
        'center_x': 100,
        'center_y': 100
    }

    def __init__(self, NIE=True):
        """

        :param NIE: bool, if True, is using the NIE analytic model. Otherwise it uses PEMD with gamma=2 from fastell4py
        """
        self._nie = NIE
        if NIE:
            from lenstronomy.LensModel.Profiles.nie import NIE
            self.profile = NIE()
        else:
            from lenstronomy.LensModel.Profiles.epl import EPL
            self.profile = EPL()
        self._s_scale = 0.0000000001
        self._gamma = 2
        super(SIE, self).__init__()

    def function(self, x, y, theta_E, e1, e2, center_x=0, center_y=0):
        """

        :param x: x-coordinate (angular coordinates)
        :param y: y-coordinate (angular coordinates)
        :param theta_E: Einstein radius
        :param e1: eccentricity
        :param e2: eccentricity
        :param center_x: centroid
        :param center_y: centroid
        :return:
        """
        if self._nie:
            return self.profile.function(x, y, theta_E, e1, e2, self._s_scale,
                                         center_x, center_y)
        else:
            return self.profile.function(x, y, theta_E, self._gamma, e1, e2,
                                         center_x, center_y)

    def derivatives(self, x, y, theta_E, e1, e2, center_x=0, center_y=0):
        """

        :param x: x-coordinate (angular coordinates)
        :param y: y-coordinate (angular coordinates)
        :param theta_E: Einstein radius
        :param e1: eccentricity
        :param e2: eccentricity
        :param center_x: centroid
        :param center_y: centroid
        :return:
        """
        if self._nie:
            return self.profile.derivatives(x, y, theta_E, e1, e2,
                                            self._s_scale, center_x, center_y)
        else:
            return self.profile.derivatives(x, y, theta_E, self._gamma, e1, e2,
                                            center_x, center_y)

    def hessian(self, x, y, theta_E, e1, e2, center_x=0, center_y=0):
        """

        :param x: x-coordinate (angular coordinates)
        :param y: y-coordinate (angular coordinates)
        :param theta_E: Einstein radius
        :param e1: eccentricity
        :param e2: eccentricity
        :param center_x: centroid
        :param center_y: centroid
        :return:
        """
        if self._nie:
            return self.profile.hessian(x, y, theta_E, e1, e2, self._s_scale,
                                        center_x, center_y)
        else:
            return self.profile.hessian(x, y, theta_E, self._gamma, e1, e2,
                                        center_x, center_y)

    @staticmethod
    def theta2rho(theta_E):
        """
        converts projected density parameter (in units of deflection) into 3d density parameter

        :param theta_E:
        :return:
        """
        fac1 = np.pi * 2
        rho0 = theta_E / fac1
        return rho0

    @staticmethod
    def mass_3d(r, rho0, e1=0, e2=0):
        """
        mass enclosed a 3d sphere or radius r

        :param r: radius in angular units
        :param rho0: density at angle=1
        :return: mass in angular units
        """
        mass_3d = 4 * np.pi * rho0 * r
        return mass_3d

    def mass_3d_lens(self, r, theta_E, e1=0, e2=0):
        """
        mass enclosed a 3d sphere or radius r given a lens parameterization with angular units

        :param r: radius in angular units
        :param theta_E: Einstein radius
        :return: mass in angular units
        """
        rho0 = self.theta2rho(theta_E)
        return self.mass_3d(r, rho0)

    def mass_2d(self, r, rho0, e1=0, e2=0):
        """
        mass enclosed projected 2d sphere of radius r

        :param r:
        :param rho0:
        :param e1:
        :param e2:
        :return:
        """
        alpha = 2 * rho0 * np.pi**2
        mass_2d = alpha * r
        return mass_2d

    def mass_2d_lens(self, r, theta_E, e1=0, e2=0):
        """

        :param r:
        :param theta_E:
        :param e1:
        :param e2:
        :return:
        """
        rho0 = self.theta2rho(theta_E)
        return self.mass_2d(r, rho0)

    def grav_pot(self, x, y, rho0, e1=0, e2=0, center_x=0, center_y=0):
        """
        gravitational potential (modulo 4 pi G and rho0 in appropriate units)

        :param x:
        :param y:
        :param rho0:
        :param e1:
        :param e2:
        :param center_x:
        :param center_y:
        :return:
        """
        x_ = x - center_x
        y_ = y - center_y
        r = np.sqrt(x_**2 + y_**2)
        mass_3d = self.mass_3d(r, rho0)
        pot = mass_3d / r
        return pot

    def density_lens(self, r, theta_E, e1=0, e2=0):
        """
        computes the density at 3d radius r given lens model parameterization.
        The integral in the LOS projection of this quantity results in the convergence quantity.

        :param r: radius in angles
        :param theta_E: Einstein radius
        :param e1: eccentricity component
        :param e2: eccentricity component
        :return: density
        """
        rho0 = self.theta2rho(theta_E)
        return self.density(r, rho0)

    @staticmethod
    def density(r, rho0, e1=0, e2=0):
        """
        computes the density

        :param r: radius in angles
        :param rho0: density at angle=1
        :return: density at r
        """
        rho = rho0 / r**2
        return rho

    @staticmethod
    def density_2d(x, y, rho0, e1=0, e2=0, center_x=0, center_y=0):
        """
        projected density

        :param x:
        :param y:
        :param rho0:
        :param e1:
        :param e2:
        :param center_x:
        :param center_y:
        :return:
        """
        x_ = x - center_x
        y_ = y - center_y
        r = np.sqrt(x_**2 + y_**2)
        sigma = np.pi * rho0 / r
        return sigma
Example #3
0
class TestSIE(object):
    """
        tests the Gaussian methods
        """
    def setup(self):
        from lenstronomy.LensModel.Profiles.sie import SIE
        from lenstronomy.LensModel.Profiles.epl import EPL
        from lenstronomy.LensModel.Profiles.nie import NIE
        self.sie = SIE(NIE=False)
        self.sie_nie = SIE(NIE=True)
        self.epl = EPL()
        self.nie = NIE()

    def test_function(self):
        x = np.array([1])
        y = np.array([2])
        theta_E = 1.
        q = 0.9
        phi_G = 1.
        e1, e2 = param_util.phi_q2_ellipticity(phi_G, q)
        values = self.sie.function(x, y, theta_E, e1, e2)
        gamma = 2
        values_spemd = self.epl.function(x, y, theta_E, gamma, e1, e2)
        assert values == values_spemd

        values_nie = self.sie_nie.function(x, y, theta_E, e1, e2)
        s_scale = 0.0000001
        values_spemd = self.nie.function(x, y, theta_E, e1, e2, s_scale)
        npt.assert_almost_equal(values_nie, values_spemd, decimal=6)

    def test_derivatives(self):
        x = np.array([1])
        y = np.array([2])
        theta_E = 1.
        q = 0.7
        phi_G = 1.
        e1, e2 = param_util.phi_q2_ellipticity(phi_G, q)
        values = self.sie.derivatives(x, y, theta_E, e1, e2)
        gamma = 2
        values_spemd = self.epl.derivatives(x, y, theta_E, gamma, e1, e2)
        assert values == values_spemd

        values = self.sie_nie.derivatives(x, y, theta_E, e1, e2)
        s_scale = 0.0000001
        values_spemd = self.nie.derivatives(x, y, theta_E, e1, e2, s_scale)
        npt.assert_almost_equal(values, values_spemd, decimal=6)

    def test_hessian(self):
        x = np.array([1])
        y = np.array([2])
        theta_E = 1.
        q = 0.7
        phi_G = 1.
        e1, e2 = param_util.phi_q2_ellipticity(phi_G, q)
        values = self.sie.hessian(x, y, theta_E, e1, e2)
        gamma = 2
        values_spemd = self.epl.hessian(x, y, theta_E, gamma, e1, e2)
        assert values[0] == values_spemd[0]

        values = self.sie_nie.hessian(x, y, theta_E, e1, e2)
        s_scale = 0.0000001
        values_spemd = self.nie.hessian(x, y, theta_E, e1, e2, s_scale)
        npt.assert_almost_equal(values, values_spemd, decimal=5)
Example #4
0
class TestEPL(object):
    """
    tests the Gaussian methods
    """
    def setup(self):
        from lenstronomy.LensModel.Profiles.epl import EPL
        self.EPL = EPL()
        from lenstronomy.LensModel.Profiles.nie import NIE
        self.NIE = NIE()

    def test_function(self):
        phi_E = 1.
        t = 1.
        q = 0.999
        phi_G = 1.
        e1, e2 = param_util.phi_q2_ellipticity(phi_G, q)
        x = np.array([1., 2])
        y = np.array([2, 0])
        values = self.EPL.function(x, y, phi_E, e1, e2, t)
        values_nie = self.NIE.function(x, y, phi_E, e1, e2, 0.)
        delta_f = values[0] - values[1]
        delta_f_nie = values_nie[0] - values_nie[1]
        npt.assert_almost_equal(delta_f, delta_f_nie, decimal=5)

        q = 0.8
        e1, e2 = param_util.phi_q2_ellipticity(phi_G, q)
        x = np.array([1., 2])
        y = np.array([2, 0])
        values = self.EPL.function(x, y, phi_E, e1, e2, t)
        values_nie = self.NIE.function(x, y, phi_E, e1, e2, 0.)
        delta_f = values[0] - values[1]
        delta_f_nie = values_nie[0] - values_nie[1]
        npt.assert_almost_equal(delta_f, delta_f_nie, decimal=5)

        q = 0.4
        e1, e2 = param_util.phi_q2_ellipticity(phi_G, q)
        x = np.array([1., 2])
        y = np.array([2, 0])
        values = self.EPL.function(x, y, phi_E, e1, e2, t)
        values_nie = self.NIE.function(x, y, phi_E, e1, e2, 0.)
        delta_f = values[0] - values[1]
        delta_f_nie = values_nie[0] - values_nie[1]
        npt.assert_almost_equal(delta_f, delta_f_nie, decimal=5)

    def test_derivatives(self):
        x = np.array([1])
        y = np.array([2])
        phi_E = 1.
        t = 1.
        q = 1.
        phi_G = 1.
        e1, e2 = param_util.phi_q2_ellipticity(phi_G, q)
        f_x, f_y = self.EPL.derivatives(x, y, phi_E, e1, e2, t)
        f_x_nie, f_y_nie = self.NIE.derivatives(x, y, phi_E, e1, e2, 0.)
        npt.assert_almost_equal(f_x, f_x_nie, decimal=4)
        npt.assert_almost_equal(f_y, f_y_nie, decimal=4)

        q = 0.7
        phi_G = 1.
        e1, e2 = param_util.phi_q2_ellipticity(phi_G, q)
        f_x, f_y = self.EPL.derivatives(x, y, phi_E, e1, e2, t)
        f_x_nie, f_y_nie = self.NIE.derivatives(x, y, phi_E, e1, e2, 0.)
        npt.assert_almost_equal(f_x, f_x_nie, decimal=4)
        npt.assert_almost_equal(f_y, f_y_nie, decimal=4)

    def test_hessian(self):
        x = np.array([1.])
        y = np.array([2.])
        phi_E = 1.
        t = 1.
        q = 0.9
        phi_G = 1.
        e1, e2 = param_util.phi_q2_ellipticity(phi_G, q)
        f_xx, f_yy, f_xy = self.EPL.hessian(x, y, phi_E, e1, e2, t)
        f_xx_nie, f_yy_nie, f_xy_nie = self.NIE.hessian(
            x, y, phi_E, e1, e2, 0.)
        npt.assert_almost_equal(f_xx, f_xx_nie, decimal=4)
        npt.assert_almost_equal(f_yy, f_yy_nie, decimal=4)
        npt.assert_almost_equal(f_xy, f_xy_nie, decimal=4)

    def test_static(self):
        x, y = 1., 1.
        phi_G, q = 0.3, 0.8
        e1, e2 = param_util.phi_q2_ellipticity(phi_G, q)
        kwargs_lens = {'theta_E': 1., 't': 1.5, 'e1': e1, 'e2': e2}
        f_ = self.EPL.function(x, y, **kwargs_lens)
        self.EPL.set_static(**kwargs_lens)
        f_static = self.EPL.function(x, y, **kwargs_lens)
        npt.assert_almost_equal(f_, f_static, decimal=8)
        self.EPL.set_dynamic()
        kwargs_lens = {'theta_E': 2., 't': 0.5, 'e1': e1, 'e2': e2}
        f_dyn = self.EPL.function(x, y, **kwargs_lens)
        assert f_dyn != f_static
Example #5
0
class TestEPL_numba(object):
    """
    tests the Gaussian methods
    """
    def setup(self):
        from lenstronomy.LensModel.Profiles.epl import EPL
        self.EPL = EPL()
        from lenstronomy.LensModel.Profiles.epl_numba import EPL_numba
        self.EPL_numba = EPL_numba()

    def test_function(self):
        phi_E = 1.
        gamma = 2.
        q = 0.999
        phi_G = 1.
        e1, e2 = param_util.phi_q2_ellipticity(phi_G, q)
        x = np.array([1., 2])
        y = np.array([2, 0])
        values = self.EPL.function(x, y, phi_E, gamma, e1, e2)
        values_nb = self.EPL_numba.function(x, y, phi_E, gamma, e1, e2)
        delta_f = values[0] - values[1]
        delta_f_nb = values_nb[0] - values_nb[1]
        npt.assert_almost_equal(delta_f, delta_f_nb, decimal=10)

        q = 0.8
        e1, e2 = param_util.phi_q2_ellipticity(phi_G, q)
        x = np.array([1., 2])
        y = np.array([2, 0])
        values = self.EPL.function(x, y, phi_E, gamma, e1, e2)
        values_nb = self.EPL_numba.function(x, y, phi_E, gamma, e1, e2)
        delta_f = values[0] - values[1]
        delta_f_nb = values_nb[0] - values_nb[1]
        npt.assert_almost_equal(delta_f, delta_f_nb, decimal=10)

        q = 0.4
        e1, e2 = param_util.phi_q2_ellipticity(phi_G, q)
        x = np.array([1., 2])
        y = np.array([2, 0])
        values = self.EPL.function(x, y, phi_E, gamma, e1, e2)
        values_nb = self.EPL_numba.function(x, y, phi_E, gamma, e1, e2)
        delta_f = values[0] - values[1]
        delta_f_nb = values_nb[0] - values_nb[1]
        npt.assert_almost_equal(delta_f, delta_f_nb, decimal=10)

    def test_derivatives(self):
        x = np.array([1])
        y = np.array([2])
        phi_E = 1.
        gamma = 1.8
        q = 1.
        phi_G = 1.
        e1, e2 = param_util.phi_q2_ellipticity(phi_G, q)
        f_x, f_y = self.EPL.derivatives(x, y, phi_E, gamma, e1, e2)
        f_x_nb, f_y_nb = self.EPL_numba.derivatives(x, y, phi_E, gamma, e1, e2)
        npt.assert_almost_equal(f_x, f_x_nb, decimal=10)
        npt.assert_almost_equal(f_y, f_y_nb, decimal=10)

        q = 0.7
        phi_G = 1.
        e1, e2 = param_util.phi_q2_ellipticity(phi_G, q)
        f_x, f_y = self.EPL.derivatives(x, y, phi_E, gamma, e1, e2)
        f_x_nb, f_y_nb = self.EPL_numba.derivatives(x, y, phi_E, gamma, e1, e2)
        npt.assert_almost_equal(f_x, f_x_nb, decimal=10)
        npt.assert_almost_equal(f_y, f_y_nb, decimal=10)

    def test_hessian(self):
        x = np.array([1.])
        y = np.array([2.])
        phi_E = 1.
        gamma = 2.2
        q = 0.9
        phi_G = 1.
        e1, e2 = param_util.phi_q2_ellipticity(phi_G, q)
        f_xx, f_xy, f_yx, f_yy = self.EPL.hessian(x, y, phi_E, gamma, e1, e2)
        f_xx_nb, f_xy_nb, f_yx_nb, f_yy_nb = self.EPL_numba.hessian(
            x, y, phi_E, gamma, e1, e2)
        npt.assert_almost_equal(f_xx, f_xx_nb, decimal=10)
        npt.assert_almost_equal(f_yy, f_yy_nb, decimal=10)
        npt.assert_almost_equal(f_xy, f_xy_nb, decimal=10)

    def test_regularization(self):

        phi_E = 1.
        gamma = 2.
        q = 1.
        phi_G = 1.
        e1, e2 = param_util.phi_q2_ellipticity(phi_G, q)

        x = 0.
        y = 0.
        f_x, f_y = self.EPL_numba.derivatives(x, y, phi_E, gamma, e1, e2)
        npt.assert_almost_equal(f_x, 0.)
        npt.assert_almost_equal(f_y, 0.)

        x = 0.
        y = 0.
        f_x, f_y = self.EPL.derivatives(x, y, phi_E, gamma, e1, e2)
        npt.assert_almost_equal(f_x, 0.)
        npt.assert_almost_equal(f_y, 0.)

        x = 0.
        y = 0.
        f_x, f_y = self.EPL.derivatives(x, y, phi_E, gamma + 0.1, e1, e2)
        npt.assert_almost_equal(f_x, 0.)
        npt.assert_almost_equal(f_y, 0.)

        x = 0.
        y = 0.
        f = self.EPL_numba.function(x, y, phi_E, gamma, e1, e2)
        npt.assert_almost_equal(f, 0.)

        x = 0.
        y = 0.
        f_xx, f_xy, f_yx, f_yy = self.EPL_numba.hessian(
            x, y, phi_E, gamma, e1, e2)
        npt.assert_almost_equal(f_xx, 1e10, decimal=10)
        npt.assert_almost_equal(f_yy, 0, decimal=10)
        npt.assert_almost_equal(
            f_xy, 0, decimal=5)  # floating point cancellation, so less precise
        # Magnification:
        npt.assert_almost_equal(1 / ((1 - f_xx) * (1 - f_yy) - f_xy**2),
                                0.,
                                decimal=10)
Example #6
0
class SIE(LensProfileBase):
    """
    class for singular isothermal ellipsoid (SIS with ellipticity)
    """
    param_names = ['theta_E', 'e1', 'e2', 'center_x', 'center_y']
    lower_limit_default = {
        'theta_E': 0,
        'e1': -0.5,
        'e2': -0.5,
        'center_x': -100,
        'center_y': -100
    }
    upper_limit_default = {
        'theta_E': 100,
        'e1': 0.5,
        'e2': 0.5,
        'center_x': 100,
        'center_y': 100
    }

    def __init__(self, NIE=True):
        """

        :param NIE: bool, if True, is using the NIE analytic model. Otherwise it uses PEMD with gamma=2 from fastell4py
        """
        self._nie = NIE
        if NIE:
            from lenstronomy.LensModel.Profiles.nie import NIE
            self.profile = NIE()
        else:
            from lenstronomy.LensModel.Profiles.epl import EPL
            self.profile = EPL()
        self._s_scale = 0.0000000001
        self._gamma = 2
        super(SIE, self).__init__()

    def function(self, x, y, theta_E, e1, e2, center_x=0, center_y=0):
        """

        :param x:
        :param y:
        :param theta_E:
        :param q:
        :param phi_G:
        :param center_x:
        :param center_y:
        :return:
        """
        if self._nie:
            return self.profile.function(x, y, theta_E, e1, e2, self._s_scale,
                                         center_x, center_y)
        else:
            return self.profile.function(x, y, theta_E, self._gamma, e1, e2,
                                         center_x, center_y)

    def derivatives(self, x, y, theta_E, e1, e2, center_x=0, center_y=0):
        """

        :param x:
        :param y:
        :param theta_E:
        :param q:
        :param phi_G:
        :param center_x:
        :param center_y:
        :return:
        """
        if self._nie:
            return self.profile.derivatives(x, y, theta_E, e1, e2,
                                            self._s_scale, center_x, center_y)
        else:
            return self.profile.derivatives(x, y, theta_E, self._gamma, e1, e2,
                                            center_x, center_y)

    def hessian(self, x, y, theta_E, e1, e2, center_x=0, center_y=0):
        """

        :param x:
        :param y:
        :param theta_E:
        :param q:
        :param phi_G:
        :param center_x:
        :param center_y:
        :return:
        """
        if self._nie:
            return self.profile.hessian(x, y, theta_E, e1, e2, self._s_scale,
                                        center_x, center_y)
        else:
            return self.profile.hessian(x, y, theta_E, self._gamma, e1, e2,
                                        center_x, center_y)

    @staticmethod
    def theta2rho(theta_E):
        """
        converts projected density parameter (in units of deflection) into 3d density parameter
        :param theta_E:
        :return:
        """
        fac1 = np.pi * 2
        rho0 = theta_E / fac1
        return rho0

    @staticmethod
    def mass_3d(r, rho0, e1=0, e2=0):
        """
        mass enclosed a 3d sphere or radius r
        :param r: radius in angular units
        :param rho0: density at angle=1
        :return: mass in angular units
        """
        mass_3d = 4 * np.pi * rho0 * r
        return mass_3d

    def mass_3d_lens(self, r, theta_E, e1=0, e2=0):
        """
        mass enclosed a 3d sphere or radius r given a lens parameterization with angular units

        :param r: radius in angular units
        :param theta_E: Einstein radius
        :return: mass in angular units
        """
        rho0 = self.theta2rho(theta_E)
        return self.mass_3d(r, rho0)

    def mass_2d(self, r, rho0, e1=0, e2=0):
        """
        mass enclosed projected 2d sphere of radius r
        :param r:
        :param rho0:
        :param a:
        :param s:
        :return:
        """
        alpha = np.pi * np.pi * 2 * rho0
        mass_2d = alpha * r
        return mass_2d

    def mass_2d_lens(self, r, theta_E, e1=0, e2=0):
        """

        :param r:
        :param theta_E:
        :return:
        """
        rho0 = self.theta2rho(theta_E)
        return self.mass_2d(r, rho0)

    def grav_pot(self, x, y, rho0, e1=0, e2=0, center_x=0, center_y=0):
        """
        gravitational potential (modulo 4 pi G and rho0 in appropriate units)
        :param x:
        :param y:
        :param rho0:
        :param a:
        :param s:
        :param center_x:
        :param center_y:
        :return:
        """
        x_ = x - center_x
        y_ = y - center_y
        r = np.sqrt(x_**2 + y_**2)
        mass_3d = self.mass_3d(r, rho0)
        pot = mass_3d / r
        return pot

    def density_lens(self, r, theta_E, e1=0, e2=0):
        """
        computes the density at 3d radius r given lens model parameterization.
        The integral in the LOS projection of this quantity results in the convergence quantity.

        :param r: radius in angles
        :param theta_E: Einstein radius
        :param e1: eccentricity component
        :param e2: eccentricity component
        :return: density
        """
        rho0 = self.theta2rho(theta_E)
        return self.density(r, rho0)

    @staticmethod
    def density(r, rho0, e1=0, e2=0):
        """
        computes the density
        :param r: radius in angles
        :param rho0: density at angle=1
        :return: density at r
        """
        rho = rho0 / r**2
        return rho

    @staticmethod
    def density_2d(x, y, rho0, e1=0, e2=0, center_x=0, center_y=0):
        """
        projected density
        :param x:
        :param y:
        :param rho0:
        :param center_x:
        :param center_y:
        :return:
        """
        x_ = x - center_x
        y_ = y - center_y
        r = np.sqrt(x_**2 + y_**2)
        sigma = np.pi * rho0 / r
        return sigma