def axes_correlated_with_input_vector(input_vectors, p=0., seed=None):
    r"""
    Calculate a list of 3d unit-vectors whose orientation is correlated
    with the orientation of `input_vectors`.

    Parameters
    ----------
    input_vectors : ndarray
        Numpy array of shape (npts, 3) storing a list of 3d vectors defining the
        preferred orientation with which the returned vectors will be correlated.
        Note that the normalization of `input_vectors` will be ignored.

    p : ndarray, optional
        Numpy array with shape (npts, ) defining the strength of the correlation
        between the orientation of the returned vectors and the z-axis.
        Default is zero, for no correlation.
        Positive (negative) values of `p` produce galaxy principal axes
        that are statistically aligned with the positive (negative) z-axis;
        the strength of this alignment increases with the magnitude of p.
        When p = 0, galaxy axes are randomly oriented.

    seed : int, optional
        Random number seed used to choose a random orthogonal direction

    Returns
    -------
    unit_vectors : ndarray
        Numpy array of shape (npts, 3)
    """

    input_unit_vectors = normalized_vectors(input_vectors)
    assert input_unit_vectors.shape[1] == 3
    npts = input_unit_vectors.shape[0]

    z_correlated_axes = axes_correlated_with_z(p, seed)

    z_axes = np.tile((0, 0, 1), npts).reshape((npts, 3))

    angles = angles_between_list_of_vectors(z_axes, input_unit_vectors)
    rotation_axes = vectors_normal_to_planes(z_axes, input_unit_vectors)
    matrices = rotation_matrices_from_angles(angles, rotation_axes)

    return rotate_vector_collection(matrices, z_correlated_axes)
예제 #2
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    def assign_positions(self, **kwargs):
        """
        assign satellite positions based on subhalo radial positions and random angular positions.
        """

        if 'table' in kwargs.keys():
            table = kwargs['table']
            halo_x = table['halo_x']
            halo_y = table['halo_y']
            halo_z = table['halo_z']
            halo_hostid = table['halo_hostid']
            halo_id = table['halo_id']
            b_to_a = table['halo_b_to_a']
            c_to_a = table['halo_c_to_a']
            halo_axisA_x = table['halo_axisA_x']
            halo_axisA_y = table['halo_axisA_y']
            halo_axisA_z = table['halo_axisA_z']
            halo_axisC_x = table['halo_axisC_x']
            halo_axisC_y = table['halo_axisC_y']
            halo_axisC_z = table['halo_axisC_z']
            concentration = table['halo_nfw_conc']
            rvir = table['halo_rvir']
            try:
                Lbox = kwargs['Lbox']
            except KeyError:
                Lbox = self._Lbox
        else:
            halo_x = kwargs['halo_x']
            halo_y = kwargs['halo_y']
            halo_z = kwargs['halo_z']
            halo_hostid = kwargs['halo_hostid']
            halo_id = kwargs['halo_id']
            b_to_a = kwargs['halo_b_to_a']
            c_to_a = kwargs['halo_c_to_a']
            halo_axisA_x = kwargs['halo_axisA_x']
            halo_axisA_y = kwargs['halo_axisA_y']
            halo_axisA_z = kwargs['halo_axisA_z']
            halo_axisC_x = kwargs['halo_axisC_x']
            halo_axisC_y = kwargs['halo_axisC_y']
            halo_axisC_z = kwargs['halo_axisC_z']
            concentration = kwargs['halo_nfw_conc']
            rvir = tabel['halo_rvir']
            try:
                Lbox = kwargs['Lbox']
            except KeyError:
                Lbox = self._Lbox

        Npts = len(halo_x)

        # get host halo properties
        inds1, inds2 = crossmatch(halo_hostid, halo_id)

        # some sub-haloes point to a host that does not exist
        no_host = ~np.in1d(halo_hostid, halo_id)
        if np.sum(no_host)>0:
            msg = ("There are {0} sub-haloes with no host halo.".format(np.sum(no_host)))
            warn(msg)

        host_halo_concentration = np.zeros(Npts)
        host_halo_concentration[inds1] = concentration[inds2]

        host_halo_rvir = np.zeros(Npts)
        host_halo_rvir[inds1] = rvir[inds2]

        host_b_to_a = np.zeros(Npts)
        host_b_to_a[inds1] = b_to_a[inds2]
        host_c_to_a = np.zeros(Npts)
        host_c_to_a[inds1] = c_to_a[inds2]

        major_axis = np.vstack((halo_axisA_x, halo_axisA_y, halo_axisA_z)).T
        minor_axis = np.vstack((halo_axisC_x, halo_axisC_y, halo_axisC_z)).T
        inter_axis = np.cross(major_axis, minor_axis)

        host_major_axis = np.zeros((Npts,3))
        host_inter_axis = np.zeros((Npts,3))
        host_minor_axis = np.zeros((Npts,3))
        host_major_axis[inds1] = major_axis[inds2]
        host_inter_axis[inds1] = inter_axis[inds2]
        host_minor_axis[inds1] = minor_axis[inds2]

        # host x,y,z-position
        halo_x[inds1] = halo_x[inds2]
        halo_y[inds1] = halo_y[inds2]
        halo_z[inds1] = halo_z[inds2]

        # host halo centric positions
        phi = np.random.uniform(0, 2*np.pi, Npts)
        uran = np.random.rand(Npts)*2 - 1

        cos_t = uran
        sin_t = np.sqrt((1.-cos_t*cos_t))

        b_to_a, c_to_a = self.anisotropy_bias_response(host_b_to_a, host_c_to_a)

        c_to_b = c_to_a/b_to_a

        # temporarily use x-axis as the major axis
        x = 1.0/c_to_a*sin_t * np.cos(phi)
        y = 1.0/c_to_b*sin_t * np.sin(phi)
        z = cos_t

        x_correlated_axes = np.vstack((x, y, z)).T

        x_axes = np.tile((1, 0, 0), Npts).reshape((Npts, 3))

        matrices = rotation_matrices_from_basis(host_major_axis,host_inter_axis,host_minor_axis)

        # rotate x-axis into the major axis
        #angles = angles_between_list_of_vectors(x_axes, major_axes)
        #rotation_axes = vectors_normal_to_planes(x_axes, major_axes)
        #matrices = rotation_matrices_from_angles(angles, rotation_axes)

        correlated_axes = rotate_vector_collection(matrices, x_correlated_axes)

        x, y, z = correlated_axes[:, 0], correlated_axes[:, 1], correlated_axes[:, 2]

        nfw = NFWPhaseSpace(conc_mass_model='direct_from_halo_catalog',)
        dimensionless_radial_distance = nfw._mc_dimensionless_radial_distance(host_halo_concentration)

        x *= dimensionless_radial_distance
        y *= dimensionless_radial_distance
        z *= dimensionless_radial_distance

        x *= host_halo_rvir
        y *= host_halo_rvir
        z *= host_halo_rvir

        a = 1
        b = b_to_a * a
        c = c_to_a * a
        T = (c**2-b**2)/(c**2-a**2)
        q = b/a
        s = c/a

        x *= np.sqrt(q*s)
        y *= np.sqrt(q*s)
        z *= np.sqrt(q*s)

        # host-halo centric radial distance
        r = np.sqrt(x*x + y*y + z*z)

        # move back into original cordinate system
        xx = halo_x + x
        yy = halo_y + y
        zz = halo_z + z

        xx[no_host] = halo_x[no_host]
        yy[no_host] = halo_y[no_host]
        zz[no_host] = halo_z[no_host]

        # account for PBCs
        xx, yy, zz = wrap_coordinates(xx, yy, zz, Lbox)

        if 'table' in kwargs.keys():
            # assign satellite galaxy positions
            try:
                mask = (table['gal_type']=='satellites')
            except KeyError:
                mask = np.array([True]*len(table))
                msg = ("`gal_type` not indicated in `table`.",
                       "The orientation is being assigned for all galaxies in the `table`.")
                print(msg)

            table['x'] = halo_x*1.0
            table['y'] = halo_y*1.0
            table['z'] = halo_z*1.0

            table['x'][mask] = xx[mask]
            table['y'][mask] = yy[mask]
            table['z'][mask] = zz[mask]

            table['r'] = 0.0
            table['r'][mask] = r[mask]

            table['halo_x'][mask] = halo_x[mask]
            table['halo_y'][mask] = halo_y[mask]
            table['halo_z'][mask] = halo_z[mask]

            return table
        else:
            x = xx
            y = yy
            z = zz
            return np.vstack((x,y,z)).T
예제 #3
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    def assign_positions(self, **kwargs):
        """
        assign satellite positions based on subhalo radial positions and random angular positions.
        """

        if 'table' in kwargs.keys():
            table = kwargs['table']
            halo_x = table['halo_x']
            halo_y = table['halo_y']
            halo_z = table['halo_z']
            halo_axisA_x = table['halo_axisA_x']
            halo_axisA_y = table['halo_axisA_y']
            halo_axisA_z = table['halo_axisA_z']
            halo_hostid = table['halo_hostid']
            halo_id = table['halo_id']
            try:
                Lbox = kwargs['Lbox']
            except KeyError:
                Lbox = self._Lbox
        else:
            halo_x = kwargs['halo_x']
            halo_y = kwargs['halo_y']
            halo_z = kwargs['halo_z']
            halo_hostid = kwargs['halo_hostid']
            halo_id = kwargs['halo_id']
            try:
                Lbox = kwargs['Lbox']
            except KeyError:
                Lbox = self._Lbox

        # get subhalo positions
        x = halo_x*1.0
        y = halo_y*1.0
        z = halo_z*1.0

        # get host halo positions
        inds1, inds2 = crossmatch(halo_hostid, halo_id)
        # x-position
        halo_x[inds1] = halo_x[inds2]
        # y-position
        halo_y[inds1] = halo_y[inds2]
        # z-position
        halo_z[inds1] = halo_z[inds2]

        # get host halo orientation
        host_halo_axisA_x = halo_axisA_x
        host_halo_axisA_x[inds1] = halo_axisA_x[inds2]
        host_halo_axisA_y = halo_axisA_y
        host_halo_axisA_y[inds1] = halo_axisA_y[inds2]
        host_halo_axisA_z = halo_axisA_z
        host_halo_axisA_z[inds1] = halo_axisA_z[inds2]
        host_halo_mjor_axes = np.vstack((halo_axisA_x,halo_axisA_y,halo_axisA_z)).T

        # calculate radial positions
        vec_r, r = radial_distance(x, y, z, halo_x, halo_y, halo_z, Lbox)

        # rotate radial vectors arond halo major axis
        N = len(x)
        rot_angles = np.random.uniform(0.0, 2*np.pi, N)
        rot_axes = host_halo_mjor_axes
        rot_m = rotation_matrices_from_angles(rot_angles,rot_axes)

        new_vec_r = rotate_vector_collection(rot_m, vec_r)
        xx = new_vec_r[:,0]
        yy = new_vec_r[:,1]
        zz = new_vec_r[:,2]

        # move back into original cordinate system
        xx = halo_x + xx
        yy = halo_y + yy
        zz = halo_z + zz

        # account for PBCs
        mask = (xx < 0.0)
        xx[mask] = xx[mask] + Lbox[0]
        mask = (xx > Lbox[0])
        xx[mask] = xx[mask] - Lbox[0]
        mask = (yy < 0.0)
        yy[mask] = yy[mask] + Lbox[1]
        mask = (yy > Lbox[1])
        yy[mask] = yy[mask] - Lbox[1]
        mask = (zz < 0.0)
        zz[mask] = zz[mask] + Lbox[2]
        mask = (zz > Lbox[2])
        zz[mask] = zz[mask] - Lbox[2]

        if 'table' in kwargs.keys():
            # assign satellite galaxy positions
            try:
                mask = (table['gal_type']=='satellites')
            except KeyError:
                mask = np.array([True]*len(table))
                msg = ("`gal_type` not indicated in `table`.",
                       "The orientation is being assigned for all galaxies in the `table`.")
                print(msg)

            table['x'] = halo_x*1.0
            table['y'] = halo_y*1.0
            table['z'] = halo_z*1.0

            table['x'][mask] = xx[mask]
            table['y'][mask] = yy[mask]
            table['z'][mask] = zz[mask]

            table['halo_x'][mask] = halo_x[mask]
            table['halo_y'][mask] = halo_y[mask]
            table['halo_z'][mask] = halo_z[mask]

            return table
        else:
            x = xx
            y = yy
            z = zz
            return np.vstack((x,y,z)).T
예제 #4
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    def assign_central_orientation(self, **kwargs):
        r"""
        Assign a set of three orthoganl unit vectors indicating the orientation
        of the galaxies' major, intermediate, and minor axis

        Parameters
        ==========
        halo_axisA_x, halo_axisA_y, halo_axisA_z :  array_like
             x,y,z components of halo alignment axis

        Returns
        =======
        major_aixs, intermediate_axis, minor_axis :  numpy nd.arrays
            arrays of galaxies' axes
        """
        if 'table' in kwargs.keys():
            table = kwargs['table']
            Ax = table[self.list_of_haloprops_needed[0]]
            Ay = table[self.list_of_haloprops_needed[1]]
            Az = table[self.list_of_haloprops_needed[2]]
        else:
            Ax = kwargs[self.list_of_haloprops_needed[0]]
            Ay = kwargs[self.list_of_haloprops_needed[1]]
            Az = kwargs[self.list_of_haloprops_needed[2]]

        # number of haloes
        N = len(Ax)

        # set prim_gal_axis orientation
        major_input_vectors = np.vstack((Ax, Ay, Az)).T
        theta_ma = self.misalignment_rvs(size=N)

        # rotate alignment vector by theta_ma
        ran_vecs = random_unit_vectors_3d(N)
        mrot = rotation_matrices_from_angles(theta_ma, ran_vecs)
        A_v = rotate_vector_collection(rotm, major_input_vectors)

        # randomly set secondary axis orientation
        B_v = random_perpendicular_directions(A_v)

        # the tertiary axis is determined
        C_v = vectors_normal_to_planes(A_v, B_v)

        # depending on the prim_gal_axis, assign correlated axes
        if self.prim_gal_axis == 'A':
            major_v = A_v
            inter_v = B_v
            minor_v = C_v
        elif self.prim_gal_axis == 'B':
            major_v = B_v
            inter_v = A_v
            minor_v = C_v
        elif self.prim_gal_axis == 'C':
            major_v = B_v
            inter_v = C_v
            minor_v = A_v
        else:
            msg = ('primary galaxy axis {0} is not recognized.'.format(
                self.prim_gal_axis))
            raise ValueError(msg)

        if 'table' in kwargs.keys():
            try:
                mask = (table['gal_type'] == self.gal_type)
            except KeyError:
                mask = np.array([True] * len(table))
                msg = (
                    "Because `gal_type` not indicated in `table`.",
                    "The orientation is being assigned for all galaxies in the `table`."
                )
                print(msg)

            # check to see if the columns exist
            for key in list(self._galprop_dtypes_to_allocate.names):
                if key not in table.keys():
                    table[key] = 0.0

            # add orientations to the galaxy table
            table['galaxy_axisA_x'][mask] = major_v[mask, 0]
            table['galaxy_axisA_y'][mask] = major_v[mask, 1]
            table['galaxy_axisA_z'][mask] = major_v[mask, 2]

            table['galaxy_axisB_x'][mask] = inter_v[mask, 0]
            table['galaxy_axisB_y'][mask] = inter_v[mask, 1]
            table['galaxy_axisB_z'][mask] = inter_v[mask, 2]

            table['galaxy_axisC_x'][mask] = minor_v[mask, 0]
            table['galaxy_axisC_y'][mask] = minor_v[mask, 1]
            table['galaxy_axisC_z'][mask] = minor_v[mask, 2]

            return table
        else:
            return major_v, inter_v, minor_v
예제 #5
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    def assign_satellite_orientation(self, **kwargs):
        r"""
        assign a a set of three orthoganl unit vectors indicating the orientation
        of the galaxies' major, intermediate, and minor axis

        Returns
        =======
        major_aixs, intermediate_axis, minor_axis :  numpy nd.arrays
            arrays of galaxies' axies
        """

        if 'table' in kwargs.keys():
            table = kwargs['table']
            try:
                Lbox = kwargs['Lbox']
            except KeyError:
                Lbox = self._Lbox
        else:
            try:
                Lbox = kwargs['Lbox']
            except KeyError:
                Lbox = self._Lbox

        # calculate the radial vector between satellites and centrals
        major_input_vectors, r = self.get_radial_vector(Lbox=Lbox, **kwargs)

        # check for length 0 radial vectors
        mask = (r <= 0.0) | (~np.isfinite(r))
        if np.sum(mask) > 0:
            major_input_vectors[mask, 0] = np.random.random((np.sum(mask)))
            major_input_vectors[mask, 1] = np.random.random((np.sum(mask)))
            major_input_vectors[mask, 2] = np.random.random((np.sum(mask)))
            msg = (
                '{0} galaxies have a radial distance equal to zero (or infinity) from their host. '
                'These galaxies will be re-assigned random alignment vectors.'.
                format(int(np.sum(mask))))
            warn(msg)

        # set prim_gal_axis orientation
        theta_ma = self.misalignment_rvs(size=N)

        # rotate alignment vector by theta_ma
        ran_vecs = random_unit_vectors_3d(N)
        mrot = rotation_matrices_from_angles(theta_ma, ran_vecs)
        A_v = rotate_vector_collection(rotm, major_input_vectors)

        # check for nan vectors
        mask = (~np.isfinite(np.sum(np.prod(A_v, axis=-1))))
        if np.sum(mask) > 0:
            A_v[mask, 0] = np.random.random((np.sum(mask)))
            A_v[mask, 1] = np.random.random((np.sum(mask)))
            A_v[mask, 2] = np.random.random((np.sum(mask)))
            msg = (
                '{0} correlated alignment axis(axes) were not found to be not finite. '
                'These will be re-assigned random vectors.'.format(
                    int(np.sum(mask))))
            warn(msg)

        # randomly set secondary axis orientation
        B_v = random_perpendicular_directions(A_v)

        # the tertiary axis is determined
        C_v = vectors_normal_to_planes(A_v, B_v)

        # use galaxy major axis as orientation axis
        major_v = A_v
        inter_v = B_v
        minor_v = C_v

        if 'table' in kwargs.keys():
            try:
                mask = (table['gal_type'] == self.gal_type)
            except KeyError:
                mask = np.array([True] * len(table))
                msg = (
                    "`gal_type` not indicated in `table`.",
                    "The orientation is being assigned for all galaxies in the `table`."
                )
                print(msg)

            # check to see if the columns exist
            for key in list(self._galprop_dtypes_to_allocate.names):
                if key not in table.keys():
                    table[key] = 0.0

            # add orientations to the galaxy table
            table['galaxy_axisA_x'][mask] = major_v[mask, 0]
            table['galaxy_axisA_y'][mask] = major_v[mask, 1]
            table['galaxy_axisA_z'][mask] = major_v[mask, 2]

            table['galaxy_axisB_x'][mask] = inter_v[mask, 0]
            table['galaxy_axisB_y'][mask] = inter_v[mask, 1]
            table['galaxy_axisB_z'][mask] = inter_v[mask, 2]

            table['galaxy_axisC_x'][mask] = minor_v[mask, 0]
            table['galaxy_axisC_y'][mask] = minor_v[mask, 1]
            table['galaxy_axisC_z'][mask] = minor_v[mask, 2]

            return table
        else:
            return major_v, inter_v, minor_v
    def mc_unit_sphere(self, Npts, **kwargs):
        r"""
        Returns Npts anisotropically distributed points on the unit sphere.

        Parameters
        ----------
        Npts : int
            Number of 3d points to generate

        seed : int, optional
            Random number seed used in the Monte Carlo realization.
            Default is None, which will produce stochastic results.

        Returns
        -------
        x, y, z : array_like
            Length-Npts arrays of the coordinate positions.
        """

        seed = kwargs.get('seed', None)

        if 'table' in kwargs:
            table = kwargs['table']
            try:
                b_to_a = table['halo_b_to_a']
            except KeyError:
                b_to_a = 1.0
            try:
                c_to_a = table['halo_c_to_a']
            except KeyError:
                c_to_a = 1.0
            try:
                halo_axisA_x = table['halo_axisA_x']
                halo_axisA_y = table['halo_axisA_y']
                halo_axisA_z = table['halo_axisA_z']
            except KeyError:
                with NumpyRNGContext(seed):
                    v = random_unit_vectors_3d(len(table))
                    halo_axisA_x = v[:, 0]
                    halo_axisA_y = v[:, 1]
                    halo_axisA_z = v[:, 2]
            try:
                halo_axisC_x = table['halo_axisC_x']
                halo_axisC_y = table['halo_axisC_y']
                halo_axisC_z = table['halo_axisC_z']
            except KeyError:
                with NumpyRNGContext(seed):
                    v = random_unit_vectors_3d(len(table))
                    halo_axisC_x = v[:, 0]
                    halo_axisC_y = v[:, 1]
                    halo_axisC_z = v[:, 2]
        else:
            try:
                b_to_a = np.atleast_1d(kwargs['b_to_a'])
            except KeyError:
                b_to_a = 1.0
            try:
                c_to_a = np.atleast_1d(kwargs['c_to_a'])
            except KeyError:
                c_to_a = 1.0
            try:
                halo_axisA_x = np.atleast_1d(kwargs['halo_axisA_x'])
                halo_axisA_y = np.atleast_1d(kwargs['halo_axisA_y'])
                halo_axisA_z = np.atleast_1d(kwargs['halo_axisA_z'])
            except KeyError:
                with NumpyRNGContext(seed):
                    v = random_unit_vectors_3d(1)
                    halo_axisC_x = v[:, 0]
                    halo_axisC_y = v[:, 1]
                    halo_axisC_z = v[:, 2]
            try:
                halo_axisC_x = np.atleast_1d(kwargs['halo_axisC_x'])
                halo_axisC_y = np.atleast_1d(kwargs['halo_axisC_y'])
                halo_axisC_z = np.atleast_1d(kwargs['halo_axisC_z'])
            except KeyError:
                with NumpyRNGContext(seed):
                    v = random_unit_vectors_3d(len(halo_axisA_x))
                    halo_axisC_x = v[:, 0]
                    halo_axisC_y = v[:, 1]
                    halo_axisC_z = v[:, 2]

        v1 = np.vstack((halo_axisA_x, halo_axisA_y, halo_axisA_z)).T
        v3 = np.vstack((halo_axisC_x, halo_axisC_y, halo_axisC_z)).T
        v2 = np.cross(v1, v3)

        with NumpyRNGContext(seed):
            phi = np.random.uniform(0, 2 * np.pi, Npts)
            uran = np.random.rand(Npts) * 2 - 1

        cos_t = uran
        sin_t = np.sqrt((1. - cos_t * cos_t))

        b_to_a, c_to_a = self.anisotropy_bias_response(b_to_a, c_to_a)

        c_to_b = c_to_a / b_to_a

        # temporarily use x-axis as the major axis
        x = 1.0 / c_to_a * sin_t * np.cos(phi)
        y = 1.0 / c_to_b * sin_t * np.sin(phi)
        z = cos_t
        x_correlated_axes = np.vstack((x, y, z)).T

        x_axes = np.tile((1, 0, 0), Npts).reshape((Npts, 3))
        major_axes = v1

        matrices = rotation_matrices_from_basis(v1, v2, v3)

        # rotate x-axis into the major axis
        #angles = angles_between_list_of_vectors(x_axes, major_axes)
        #rotation_axes = vectors_normal_to_planes(x_axes, major_axes)
        #matrices = rotation_matrices_from_angles(angles, rotation_axes)

        correlated_axes = rotate_vector_collection(matrices, x_correlated_axes)
        #correlated_axes = x_correlated_axes

        return correlated_axes[:, 0], correlated_axes[:, 1], correlated_axes[:,
                                                                             2]