Python units.K属性代码示例

# 需要导入模块: from astropy import units [as 别名]
# 或者: from astropy.units import K [as 别名]
def stellarTeff(self, sInds):
        """Calculate the effective stellar temperature based on B-V color.
        
        This method uses the empirical fit from Ballesteros (2012) doi:10.1209/0295-5075/97/34008
        
        Args:
            sInds (integer ndarray):
                Indices of the stars of interest
        
        Returns:
            Quantity array:
                Stellar effective temperatures in degrees K
        
        """
        
        # cast sInds to array
        sInds = np.array(sInds, ndmin=1, copy=False)
        
        Teff = 4600.0*u.K * (1.0/(0.92*self.BV[sInds] + 1.7) + 1.0/(0.92*self.BV[sInds] + 0.62))
        
        return Teff 

# 需要导入模块: from astropy import units [as 别名]
# 或者: from astropy.units import K [as 别名]
def prepare_quantity(value, units=None, name_val=None):
    """ The function verifys that a
    """
    if value is None:
        return None

    if isinstance(value, u.Quantity):
        if units in [u.K, u.deg_C, u.Kelvin, u.Celsius, u.imperial.deg_F]:
            return value.to(units, equivalencies=u.temperature()).value
        else:
            return value.to(units).value

    elif isinstance(value, numbers.Number) and units is not None:
        return value
    elif isinstance(value, np.ndarray) and units is not None:
        return value
    elif isinstance(value, list) and units is not None:
        return np.array([prepare_quantity(v, units, name_val) for v in value])
    elif isinstance(value, tuple) and units is not None:
        return np.array([prepare_quantity(v, units, name_val) for v in value])
    else:
        raise ValueError('%s has not the correct format. It must be a value,'
                         'sequence, array, or a Quantity with %s units' %
                         (name_val, str(units))) 

# 需要导入模块: from astropy import units [as 别名]
# 或者: from astropy.units import K [as 别名]
def calc_brightness_ratio_from_Teff(Teff_1, Teff_2, plot=False):

    bandpass = np.genfromtxt('tess-response-function-v1.0.csv', delimiter=',', names=['wavelength','transmission'])
    wavelength_grid = np.arange(500,2000,1)
    
    if plot:
        fig, ax = plt.subplots()
        ax.plot(list(bandpass['wavelength'])+[2000], list(bandpass['transmission'])+[0], lw=2)
        ax.set(ylabel='TESS Transmission')
        ax2 = ax.twinx()
        ax2.plot(wavelength_grid, blackbody_lambda(wavelength_grid*u.nm, Teff_1*u.K), 'r-', lw=2, color='darkorange')
        ax2.plot(wavelength_grid, blackbody_lambda(wavelength_grid*u.nm, Teff_2*u.K), 'r-', lw=2, color='brown')
        ax2.set(ylabel='Blackbody Flux\n'+r'($erg \, cm^{-2} \, s^{-1} \, A^{-1} \, sr^{-1}$)')
    
    int1 = np.trapz(bandpass['transmission']*u.nm*blackbody_lambda(bandpass['wavelength']*u.nm, Teff_1*u.K), x=bandpass['wavelength']*u.nm, dx=np.diff(bandpass['wavelength']*u.nm))
    int2 = np.trapz(bandpass['transmission']*u.nm*blackbody_lambda(bandpass['wavelength']*u.nm, Teff_2*u.K), x=bandpass['wavelength']*u.nm, dx=np.diff(bandpass['wavelength']*u.nm))
    sbratio = int2/int1
    
    return sbratio 

# 需要导入模块: from astropy import units [as 别名]
# 或者: from astropy.units import K [as 别名]
def Tcmb(self, z):
        """ Return the CMB temperature at redshift ``z``.

        Parameters
        ----------
        z : array_like
          Input redshifts.

        Returns
        -------
        Tcmb : `~astropy.units.Quantity`
          The temperature of the CMB in K.
        """

        if isiterable(z):
            z = np.asarray(z)
        return self._Tcmb0 * (1. + z) 

# 需要导入模块: from astropy import units [as 别名]
# 或者: from astropy.units import K [as 别名]
def Tnu(self, z):
        """ Return the neutrino temperature at redshift ``z``.

        Parameters
        ----------
        z : array_like
          Input redshifts.

        Returns
        -------
        Tnu : `~astropy.units.Quantity`
          The temperature of the cosmic neutrino background in K.
        """

        if isiterable(z):
            z = np.asarray(z)
        return self._Tnu0 * (1. + z) 

# 需要导入模块: from astropy import units [as 别名]
# 或者: from astropy.units import K [as 别名]
def test_ocurv():
    # Test Ok evolution
    # Flat, boring case
    tcos = core.FlatLambdaCDM(70.0, 0.3)
    assert allclose(tcos.Ok0, 0.0)
    assert allclose(tcos.Ok(0), 0.0)
    z = np.array([0.0, 0.5, 1.0, 2.0])
    assert allclose(tcos.Ok(z), [0.0, 0.0, 0.0, 0.0],
                    rtol=1e-6)

    # Not flat
    tcos = core.LambdaCDM(70.0, 0.3, 0.5, Tcmb0=u.Quantity(0.0, u.K))
    assert allclose(tcos.Ok0, 0.2)
    assert allclose(tcos.Ok(0), 0.2)
    assert allclose(tcos.Ok(z), [0.2, 0.22929936, 0.21621622, 0.17307692],
                    rtol=1e-4)

    # Test the sum; note that Ogamma/Onu are 0
    assert allclose(tcos.Ok(z) + tcos.Om(z) + tcos.Ode(z),
                    [1.0, 1.0, 1.0, 1.0], rtol=1e-5) 

# 需要导入模块: from astropy import units [as 别名]
# 或者: from astropy.units import K [as 别名]
def test_blackbody_scipy():
    """Test Planck function.

    .. note:: Needs ``scipy`` to work.

    """
    flux_unit = u.Watt / (u.m ** 2 * u.um)
    wave = np.logspace(0, 8, 100000) * u.AA
    temp = 100. * u.K
    with np.errstate(all='ignore'):
        bb_nu = blackbody_nu(wave, temp) * u.sr
    flux = bb_nu.to(flux_unit, u.spectral_density(wave)) / u.sr

    lum = wave.to(u.um)
    intflux = integrate.trapz(flux.value, x=lum.value)
    ans = const.sigma_sb * temp ** 4 / np.pi
    np.testing.assert_allclose(intflux, ans.value, rtol=0.01)  # 1% accuracy 

# 需要导入模块: from astropy import units [as 别名]
# 或者: from astropy.units import K [as 别名]
def test_blackbody_exceptions_and_warnings():
    """Test exceptions."""

    # Negative temperature
    with pytest.raises(ValueError) as exc:
        blackbody_nu(1000 * u.AA, -100)
    assert exc.value.args[0] == 'Temperature should be positive: -100.0 K'

    # Zero wavelength given for conversion to Hz
    with catch_warnings(AstropyUserWarning) as w:
        blackbody_nu(0 * u.AA, 5000)
    assert len(w) == 1
    assert 'invalid' in w[0].message.args[0]

    # Negative wavelength given for conversion to Hz
    with catch_warnings(AstropyUserWarning) as w:
        blackbody_nu(-1. * u.AA, 5000)
    assert len(w) == 1
    assert 'invalid' in w[0].message.args[0] 

# 需要导入模块: from astropy import units [as 别名]
# 或者: from astropy.units import K [as 别名]
def test_blackbody_overflow():
    """Test Planck function with overflow."""
    photlam = u.photon / (u.cm ** 2 * u.s * u.AA)
    wave = [0.0, 1000.0, 100000.0, 1e55]  # Angstrom
    temp = 10000.0  # Kelvin
    bb = BlackBody(temperature=temp * u.K, scale=1.0)
    with pytest.warns(
            AstropyUserWarning,
            match=r'Input contains invalid wavelength/frequency value\(s\)'):
        with np.errstate(all="ignore"):
            bb_lam = bb(wave) * u.sr
    flux = bb_lam.to(photlam, u.spectral_density(wave * u.AA)) / u.sr

    # First element is NaN, last element is very small, others normal
    assert np.isnan(flux[0])
    with np.errstate(all="ignore"):
        assert np.log10(flux[-1].value) < -134
    np.testing.assert_allclose(
        flux.value[1:-1], [0.00046368, 0.04636773], rtol=1e-3
    )  # 0.1% accuracy in PHOTLAM/sr
    with np.errstate(all="ignore"):
        flux = bb(1.0 * u.AA)
    assert flux.value == 0 

# 需要导入模块: from astropy import units [as 别名]
# 或者: from astropy.units import K [as 别名]
def test_swapped_args_brightness_temperature():
    """
    #5173 changes the order of arguments but accepts the old (deprecated) args
    """
    omega_B = np.pi * (50 * u.arcsec) ** 2
    nu = u.GHz * 5
    tb = 7.052587837212582 * u.K

    with catch_warnings(AstropyDeprecationWarning) as w:
        result = (1*u.Jy).to(
            u.K, equivalencies=u.brightness_temperature(omega_B, nu))
        roundtrip = result.to(
            u.Jy, equivalencies=u.brightness_temperature(omega_B, nu))
        assert len(w) == 2
    np.testing.assert_almost_equal(tb.value, result.value)
    np.testing.assert_almost_equal(roundtrip.value, 1) 

# 需要导入模块: from astropy import units [as 别名]
# 或者: from astropy.units import K [as 别名]
def main():
    w,h = (2056,1024)
    l_0 = 0.

    # Create a grid of coordinates
    print('Creating grid of coordinates...')
    l = np.linspace(-180.+l_0, 180.+l_0, 2*w)
    b = np.linspace(-90., 90., 2*h+2)
    b = b[1:-1]
    l,b = np.meshgrid(l, b)

    l += (np.random.random(l.shape) - 0.5) * 360./(2.*w)
    b += (np.random.random(l.shape) - 0.5) * 180./(2.*h)

    coords = SkyCoord(l*u.deg, b*u.deg, frame='galactic')

    planck_components = [
        ('ebv', 0., 1.5),
        ('radiance', 0., 1.5),
        ('tau', 0., 1.5),
        ('temp', 15.*u.K, 25.*u.K),
        ('err_temp', 0.*u.K, 4.*u.K),
        ('beta', 1., 3.),
        ('err_beta', 0., 0.2)]

    for component,vmin,vmax in planck_components:
        # Set up Planck query object
        print('Loading Planck map...')
        planck = PlanckQuery(component=component)

        print('Querying map...')
        res = planck.query(coords)

        # Convert the output array to a PIL image and save
        print('Saving image...')
        img = numpy2pil(res[::-1,::-1], vmin, vmax)
        img = img.resize((w,h), resample=PIL.Image.LANCZOS)
        fname = 'planck_{}.png'.format(component)
        img.save(fname)

    return 0 

# 需要导入模块: from astropy import units [as 别名]
# 或者: from astropy.units import K [as 别名]
def fgk_filter(self):
        """Includes only F, G, K spectral type stars in Target List
        
        """
        
        spec = np.array(list(map(str, self.Spec)))
        iF = np.where(np.core.defchararray.startswith(spec, 'F'))[0]
        iG = np.where(np.core.defchararray.startswith(spec, 'G'))[0]
        iK = np.where(np.core.defchararray.startswith(spec, 'K'))[0]
        i = np.append(np.append(iF, iG), iK)
        i = np.unique(i)
        self.revise_lists(i) 

# 需要导入模块: from astropy import units [as 别名]
# 或者: from astropy.units import K [as 别名]
def swoops_ions(starttime, endtime):
    """
    Import SWOOPS ion data.

    Parameters
    ----------
    starttime : datetime
        Start of interval
    endtime : datetime
        End of interval

    Returns
    -------
    data : :class:`~sunpy.timeseries.TimeSeries`
        Requested data
    """

    units = OrderedDict([('T_p_large', u.K), ('T_p_small', u.K),
                        ('v_t', u.km / u.s), ('v_r', u.km / u.s),
                        ('v_n', u.km / u.s), ('r', u.au),
                        ('n_a', u.cm**-3), ('n_p', u.cm**-3),
                        ('hlat', u.deg),
                        ('hlon', u.deg),
                        ('iqual', u.dimensionless_unscaled)])
    downloader = _swoopsionDownloader(units)
    return downloader.load(starttime, endtime) 

# 需要导入模块: from astropy import units [as 别名]
# 或者: from astropy.units import K [as 别名]
def __init__(self, probe):
        _check_probe(probe, ['8'])
        self.probe = probe

        self.units = OrderedDict(
            [('sw_flag', u.dimensionless_unscaled),
             ('x_gse', u.R_earth), ('y_gse', u.R_earth),
             ('z_gse', u.R_earth), ('y_gsm', u.R_earth),
             ('z_gsm', u.R_earth), ('Nm', u.dimensionless_unscaled),
             ('<|B|>', u.nT), ('|<B>|', u.nT), ('<B_lat>', u.nT),
             ('<B_long>', u.nT), ('Bx_gse', u.nT), ('By_gse', u.nT),
             ('Bz_gse', u.nT), ('By_gsm', u.nT), ('Bz_gsm', u.nT),
             ('sigma|B|', u.nT), ('sigma B', u.nT),
             ('sigma B_x', u.nT), ('sigma B_y', u.nT),
             ('sigma B_z', u.nT),
             ('plas_reg', u.dimensionless_unscaled),
             ('Npp', u.dimensionless_unscaled),
             ('v_fit', u.km / u.s), ('vx_fit_gse', u.km / u.s),
             ('vy_fit_gse', u.km / u.s), ('vz_fit_gse', u.km / u.s),
             ('vlong_fit', u.deg), ('vlat_fit', u.deg),
             ('np_fit', u.cm**-3), ('Tp_fit', u.K),
             ('v_mom', u.km / u.s), ('vx_mom_gse', u.km / u.s),
             ('vy_mom_gse', u.km / u.s), ('vz_mom_gse', u.km / u.s),
             ('vlong_mom', u.deg), ('vlat_mom', u.deg),
             ('np_mom', u.cm**-3), ('Tp_mom', u.K),
             ('FCp', u.dimensionless_unscaled),
             ('DWp', u.dimensionless_unscaled)]) 

# 需要导入模块: from astropy import units [as 别名]
# 或者: from astropy.units import K [as 别名]
def __init__(self, probe):
        self.probe = _check_probe(probe)
        self.units = OrderedDict([
            ('B instrument', u.dimensionless_unscaled),
            ('Bx', u.nT), ('By', u.nT), ('Bz', u.nT),
            ('sigma B', u.nT),
            ('Ion instrument', u.dimensionless_unscaled),
            ('Status', u.dimensionless_unscaled),
            ('Tp_par', u.K), ('Tp_perp', u.K),
            ('carrot', u.dimensionless_unscaled),
            ('r_sun', u.AU), ('clat', u.deg),
            ('clong', u.deg), ('earth_he_angle', u.deg),
            ('n_p', u.cm**-3), ('vp_x', u.km / u.s),
            ('vp_y', u.km / u.s), ('vp_z', u.km / u.s),
            ('vth_p_par', u.km / u.s), ('vth_p_perp', u.km / u.s)])