Exemplo n.º 1
0
def real_spec(request):
    band = request.param
    wav, flux = load_aces_spectrum([3900, 4.5, 0.0, 0])
    wav, flux = wav_selector(wav, flux, *band_limits(band))
    flux = flux / snr_constant_band(wav, flux, 100, band)
    atm = Atmosphere.from_band(band).at(wav)
    return wav, flux, atm.transmission
Exemplo n.º 2
0
def test_wav_selector(x, y, wav_min, wav_max):
    """Test some properties of wavelength selector."""
    y = [xi + y for xi in x]  # just to make y different
    x1, y1 = utils.wav_selector(x, y, wav_min, wav_max)

    assert all(x1 >= wav_min)
    assert all(x1 <= wav_max)
    assert len(x1) == len(y1)
    assert isinstance(x1, np.ndarray)
    assert isinstance(y1, np.ndarray)
Exemplo n.º 3
0
def convolution(
    wav: ndarray,
    flux: ndarray,
    vsini: float,
    R: float,
    band: str = "All",
    *,
    epsilon: float = 0.6,
    fwhm_lim: float = 5.0,
    num_procs: Optional[int] = None,
    normalize: bool = True,
):
    """Perform convolution of spectrum.

    Rotational convolution followed by a Gaussian of a specified resolution R.

    Parameters
    ----------
    wav: ndarray
        Wavelength in microns
    flux: ndarray
        Photon flux
    vsini: float
        Rotational velocity in km/s.
    R: int
        Resolution of instrumental profile.
    band: str
        Wavelength band to choose, default="All"
    epsilon: float (default = 0.6)
        Limb darkening coefficient
    fwhm_lim: float (default = 5.0)
        FWHM limit for instrument broadening.
    normalize: bool (default = True)
        Area normalize the broadening kernels (corrects for unequal sampling of position).
    num_procs: int, None
        Number of processes to use with multiprocess.
        If None it is assigned to 1 less then total number of cores.
        If num_procs = 0, then multiprocess is not used.

    Returns
    -------
    wav_band: ndarray
        Wavelength for the selected band.
    flux_band: ndarray
        Original flux for the selected band.
    flux_conv: ndarray
        Convolved flux for the selected band.
    """

    wav_band, flux_band = band_selector(wav, flux, band)

    # We need to calculate the fwhm at this value in order to set the starting point for the convolution
    fwhm_min = wav_band[0] / R  # fwhm at the extremes of vector
    fwhm_max = wav_band[-1] / R

    # performing convolution with rotation kernel
    print(
        "Starting the Rotation convolution for vsini={0:.2f}...".format(vsini))

    delta_lambda_min = wav_band[0] * vsini / c_kmps
    delta_lambda_max = wav_band[-1] * vsini / c_kmps

    # widest wavelength bin for the rotation convolution
    lower_lim = wav_band[0] - delta_lambda_min - fwhm_lim * fwhm_min
    upper_lim = wav_band[-1] + delta_lambda_max + fwhm_lim * fwhm_max
    wav_ext_rotation, flux_ext_rotation = wav_selector(wav, flux, lower_lim,
                                                       upper_lim)

    # wide wavelength bin for the resolution_convolution
    lower_lim = wav_band[0] - fwhm_lim * fwhm_min
    upper_lim = wav_band[-1] + fwhm_lim * fwhm_max
    extended_wav, __ = wav_selector(wav, flux, lower_lim, upper_lim)

    # rotational convolution
    flux_conv_rot = rotational_convolution(
        extended_wav,
        wav_ext_rotation,
        flux_ext_rotation,
        vsini,
        epsilon=epsilon,
        num_procs=num_procs,
        normalize=normalize,
    )

    print("Starting the Resolution convolution...")

    flux_conv_res = resolution_convolution(
        wav_band,
        extended_wav,
        flux_conv_rot,
        R,
        fwhm_lim=fwhm_lim,
        num_procs=num_procs,
        normalize=normalize,
    )

    return wav_band, flux_band, flux_conv_res
Exemplo n.º 4
0
def convolution(
    wav: ndarray,
    flux: ndarray,
    vsini: float,
    R: float,
    band: str = "All",
    *,
    epsilon: float = 0.6,
    fwhm_lim: float = 5.0,
    num_procs: Optional[Union[int, joblib.parallel.Parallel]] = None,
    normalize: bool = True,
    verbose: bool = True,
):
    r"""Perform rotational then Instrumental broadening with convolutions.

    Parameters
    ----------
    wav: ndarray
        Wavelength array.
    flux: ndarray
        Flux array.
    vsini: float
        Rotational velocity in km/s.
    R: int
        Resolution of instrumental profile.
    band: str
        Wavelength band to choose, default is "All".
    epsilon: float
        Limb darkening coefficient. Default is 0.6.
    fwhm_lim: float
        FWHM limit for instrument broadening. Default is 5.0.
    normalize: bool
        Area normalize the broadening kernel. This corrects for kernel area with unequal wavelength spacing.
        Default is True.
    num_procs: int, None or joblib.parallel.Parallel.
        Number of processes to use, n_job parameter in joblib.
        If num_procs =  1, then a single core is used.
        Can also be a joblib.parallel.Parallel instance.
    verbose: bool
        Show the tqdm progress bar. Default is True.

    Returns
    -------
    wav_band: ndarray
        Wavelength for the selected band.
    flux_band: ndarray
        Original flux for the selected band.
    flux_conv: ndarray
        Convolved flux for the selected band.
    """

    wav_band, flux_band = band_selector(wav, flux, band)

    # Calculate FWHM at each end for the convolution
    fwhm_min = wav_band[0] / R  # fwhm at the extremes of vector
    fwhm_max = wav_band[-1] / R

    # performing convolution with rotation kernel
    if verbose:
        print("Starting the Rotation convolution for vsini={0:.2f}...".format(
            vsini))

    delta_lambda_min = wav_band[0] * vsini / c_kmps
    delta_lambda_max = wav_band[-1] * vsini / c_kmps

    # widest wavelength bin for the rotation convolution
    lower_lim = wav_band[0] - delta_lambda_min - fwhm_lim * fwhm_min
    upper_lim = wav_band[-1] + delta_lambda_max + fwhm_lim * fwhm_max
    wav_ext_rotation, flux_ext_rotation = wav_selector(wav, flux, lower_lim,
                                                       upper_lim)

    # wide wavelength bin for the resolution_convolution
    lower_lim = wav_band[0] - fwhm_lim * fwhm_min
    upper_lim = wav_band[-1] + fwhm_lim * fwhm_max
    extended_wav, __ = wav_selector(wav, flux, lower_lim, upper_lim)

    # rotational convolution
    flux_conv_rot = rotational_convolution(
        extended_wav,
        wav_ext_rotation,
        flux_ext_rotation,
        vsini,
        epsilon=epsilon,
        num_procs=num_procs,
        normalize=normalize,
        verbose=verbose,
    )
    if verbose:
        print("Starting the Resolution convolution...")

    flux_conv_res = resolution_convolution(
        wav_band,
        extended_wav,
        flux_conv_rot,
        R,
        fwhm_lim=fwhm_lim,
        num_procs=num_procs,
        normalize=normalize,
        verbose=verbose,
    )

    return wav_band, flux_band, flux_conv_res