def __getitem__(self, item):
if item not in self.valid_keys:
raise KeyError('{} not a valid item for CCFContainer!'.format(item))
if item == 'ml' and self.ml is not None:
return DataStructures.xypoint(x=self.x, y=self.ml)
elif item == 'dc' and self.dc is not None:
return DataStructures.xypoint(x=self.x, y=self.dc)
elif item == 'simple' and self.simple is not None:
return DataStructures.xypoint(x=self.x, y=self.simple)
elif item == 'weighted' and self.weighted is not None:
return DataStructures.xypoint(x=self.x, y=self.weighted)
elif item == 'simple-weighted' and self.simple_weighted is not None:
return DataStructures.xypoint(x=self.x, y=self.simple_weighted)
return None # We should never get here...
def Interpolate_Old(self, dictionary, SpT):
# First, we must convert the relations above into a monotonically increasing system
# Just add ten when we get to each new spectral type
relation = DataStructures.xypoint(len(dictionary))
# Strip the spectral type of the luminosity class information
SpT = re.search("[A-Z]([0-9]\.?[0-9]*)", SpT).group()
xpoints = []
ypoints = []
for key, index in zip(dictionary, range(len(dictionary))):
# Convert key to a number
xpoints.append(self.SpT_To_Number(key))
ypoints.append(dictionary[key])
sorting_indices = [i[0] for i in sorted(enumerate(xpoints), key=lambda x: x[1])]
for index in range(len(dictionary)):
i = sorting_indices[index]
relation.x[index] = xpoints[i]
relation.y[index] = ypoints[i]
RELATION = UnivariateSpline(relation.x, relation.y, s=0)
spnum = self.SpT_To_Number(SpT)
if spnum > 0:
return RELATION(spnum)
else:
return np.nan
def astropy_smooth(data, vel, linearize=False, kernel=convolution.Gaussian1DKernel, **kern_args):
"""
Smooth using a gaussian filter, using astropy.
Parameters:
===========
- data: kglib.utils.DataStructures.xypoint instance
The data to smooth.
- vel: float
The velocity scale to smooth out.
Can either by an astropy quantity or a float in km/s
- linearize: boolean
If True, we will put the data in a constant
log-wavelength spacing grid before smoothing.
The output has the same spacing as the input
regardless of this variable.
- kernel: astropy.convolution kernel
The astropy kernel to use. The default is the
Gaussian1DKernel.
- kern_args: Additional kernel arguments beyond width
Returns:
========
A smoothed version of the data, on the same wavelength grid as the data
"""
if linearize:
original_data = data.copy()
datafcn = spline(data.x, data.y, k=3)
linear = DataStructures.xypoint(data.x.size)
linear.x = np.logspace(np.log10(data.x[0]), np.log10(data.x[-1]), linear.size())
linear.y = datafcn(linear.x)
data = linear
# Figure out feature size in pixels
if not isinstance(vel, u.quantity.Quantity):
vel *= u.km / u.second
featuresize = (vel / constants.c).decompose().value
dlam = np.log(data.x[1] / data.x[0])
Npix = featuresize / dlam
# Make kernel and smooth
kern = kernel(Npix, **kern_args)
smoothed = convolution.convolve(data.y, kern, boundary='extend')
if linearize:
fcn = spline(data.x, smoothed)
return fcn(original_data.x)
return smoothed
def IterativeLowPass(data, vel, numiter=100, lowreject=3, highreject=3, width=5, linearize=False):
"""
An iterative version of LowPassFilter.
It will ignore outliers in the low pass filter. New parameters that are
not described in the docstring fro LowPassFilter are:
Parameters:
===========
- numiter: integer
The maximum number of iterations to take
- lowreject: integer
How many sigma below the current filtered curve do we
count as bad and ignore in the next iteration?
- highreject: integer
How many sigma above the current filtered curve do we
count as bad and ignore in the next iteration?
"""
datacopy = data.copy()
if linearize:
datafcn = spline(datacopy.x, datacopy.y, k=3)
errorfcn = spline(datacopy.x, datacopy.err, k=1)
contfcn = spline(datacopy.x, datacopy.cont, k=1)
linear = DataStructures.xypoint(datacopy.x.size)
linear.x = np.linspace(datacopy.x[0], datacopy.x[-1], linear.size())
linear.y = datafcn(linear.x)
linear.err = errorfcn(linear.x)
linear.cont = contfcn(linear.x)
datacopy = linear.copy()
done = False
iter = 0
datacopy.cont = FittingUtilities.Continuum(datacopy.x, datacopy.y, fitorder=9, lowreject=2.5, highreject=5)
while not done and iter < numiter:
done = True
iter += 1
smoothed = LowPassFilter(datacopy, vel, width=width)
residuals = datacopy.y / smoothed
mean = np.mean(residuals)
std = np.std(residuals)
badpoints = np.where(np.logical_or((residuals - mean) < -lowreject * std, residuals - mean > highreject * std))[
0]
if badpoints.size > 0:
done = False
datacopy.y[badpoints] = smoothed[badpoints]
if linearize:
return linear.x, smoothed
else:
return smoothed
def __call__(self, T, metal, vsini=0.0, return_xypoint=True, **kwargs):
"""
Given parameters, return an interpolated spectrum
If return_xypoint is False, then it will only return
a numpy.ndarray with the spectrum
Before interpolating, we will do some error checking to make
sure the requested values fall within the grid
"""
# Scale the requested values
T = (T - self.T_scale[0]) / self.T_scale[1]
metal = (metal - self.metal_scale[0]) / self.metal_scale[1]
# Get the minimum and maximum values in the grid
T_min = min(self.grid[:, 0])
T_max = max(self.grid[:, 0])
metal_min = min(self.grid[:, 1])
metal_max = max(self.grid[:, 1])
input_list = (T, metal)
# Check to make sure the requested values fall within the grid
if (T_min <= T <= T_max and
metal_min <= metal <= metal_max):
y = self.interpolator(input_list)
else:
if self.debug:
warnings.warn("The requested parameters fall outside the model grid. Results may be unreliable!")
print(T, T_min, T_max)
print(metal, metal_min, metal_max)
y = self.NN_interpolator(input_list)
# Test to make sure the result is valid. If the requested point is
# outside the Delaunay triangulation, it will return NaN's
if np.any(np.isnan(y)):
if self.debug:
warnings.warn("Found NaNs in the interpolated spectrum! Falling back to Nearest Neighbor")
y = self.NN_interpolator(input_list)
model = DataStructures.xypoint(x=self.xaxis, y=y)
vsini *= units.km.to(units.cm)
model = Broaden.RotBroad(model, vsini, linear=self.rebin)
# Return the appropriate object
if return_xypoint:
return model
else:
return model.y
def process_model(model, data, vsini_model=None, resolution=None, vsini_primary=None,
maxvel=1000.0, debug=False, logspace=True):
"""
Process a stellar model to prepare it for cross correlation
Parameters:
- model: string, or kglib.utils.DataStructures.xypoint instance
If a string, should give the path to an ascii file with the model
Otherwise, should hold the model data
- data: list of kglib.utils.DataStructures.xypoint instances
The already-processed data.
- vsini_model: float
The rotational velocity to apply to the model spectrum
- vsini_primary: float
The rotational velocity of the primary star
- resolution: float
The detector resolution in $\lambda / \Delta \lambda$
- maxvel: float
The maximum velocity to include in the eventual CCF.
This is used to trim the data appropriately for each echelle order.
- debug: boolean
Print some extra stuff?
- logspace: boolean
Rebin the model to constant log-spacing?
Returns:
========
A list of kglib.utils.DataStructures.xypoint instances with the processed model.
"""
# Read in the model if necessary
if isinstance(model, str):
if debug:
print("Reading in the input model from %s" % model)
x, y = np.loadtxt(model, usecols=(0, 1), unpack=True)
x = x * u.angstrom.to(u.nm)
y = 10 ** y
left = np.searchsorted(x, data[0].x[0] - 10)
right = np.searchsorted(x, data[-1].x[-1] + 10)
model = DataStructures.xypoint(x=x[left:right], y=y[left:right])
elif not isinstance(model, DataStructures.xypoint):
raise TypeError(
"Input model is of an unknown type! Must be a DataStructures.xypoint or a string with the filename.")
# Linearize the x-axis of the model (in log-spacing)
if logspace:
if debug:
print("Linearizing model")
xgrid = np.logspace(np.log10(model.x[0]), np.log10(model.x[-1]), model.size())
model = FittingUtilities.RebinData(model, xgrid)
# Broaden
if vsini_model is not None and vsini_model > 1.0 * u.km.to(u.cm):
if debug:
print("Rotationally broadening model to vsini = %g km/s" % (vsini_model * u.cm.to(u.km)))
model = Broaden.RotBroad(model, vsini_model, linear=True)
# Reduce resolution
if resolution is not None and 5000 < resolution < 500000:
if debug:
print("Convolving to the detector resolution of %g" % resolution)
model = FittingUtilities.ReduceResolutionFFT(model, resolution)
# Divide by the same smoothing kernel as we used for the data
if vsini_primary is not None:
smoothed = HelperFunctions.astropy_smooth(model, vel=SMOOTH_FACTOR * vsini_primary, linearize=False)
model.y += model.cont.mean() - smoothed
model.cont = np.ones(model.size()) * model.cont.mean()
# Rebin subsets of the model to the same spacing as the data
model_orders = []
model_fcn = spline(model.x, model.y)
if debug:
model.output("Test_model.dat")
for i, order in enumerate(data):
if debug:
sys.stdout.write("\rGenerating model subset for order %i in the input data" % (i + 1))
sys.stdout.flush()
# Find how much to extend the model so that we can get maxvel range.
dlambda = order.x[order.size() / 2] * maxvel * 1.5 / 3e5
left = np.searchsorted(model.x, order.x[0] - dlambda)
right = np.searchsorted(model.x, order.x[-1] + dlambda)
right = min(right, model.size() - 2)
# Figure out the log-spacing of the data
logspacing = np.log(order.x[1] / order.x[0])
# Finally, space the model segment with the same log-spacing
start = np.log(model.x[left])
end = np.log(model.x[right])
xgrid = np.exp(np.arange(start, end + logspacing, logspacing))
segment = DataStructures.xypoint(x=xgrid, y=model_fcn(xgrid))
segment.cont = FittingUtilities.Continuum(segment.x, segment.y, lowreject=1.5, highreject=5, fitorder=2)
model_orders.append(segment)
print("\n")
return model_orders
def HighPassFilter(data, vel, width=5, linearize=False):
"""
Function to apply a high-pass filter to data.
Parameters:
===========
- data: kglib.utils.DataStructures.xypoint instance
The data to filter.
- vel: float
The width of the features to smooth out, in velocity space (in cm/s).
- width: integer
How long it takes the filter to cut off, in units of wavenumber.
- linearize: boolean
Do we need to resample the data to a constant wavelength spacing
before filtering? Set to True if the data is unevenly sampled.
Returns:
========
If linearize = True: Returns a numpy.ndarray with the new x-axis, and the filtered data
Otherwise: Returns just a numpy.ndarray with the filtered data.
"""
if linearize:
original_data = data.copy()
datafcn = spline(data.x, data.y, k=3)
errorfcn = spline(data.x, data.err, k=3)
contfcn = spline(data.x, data.cont, k=3)
linear = DataStructures.xypoint(data.x.size)
linear.x = np.linspace(data.x[0], data.x[-1], linear.size())
linear.y = datafcn(linear.x)
linear.err = errorfcn(linear.x)
linear.cont = contfcn(linear.x)
data = linear
# Figure out cutoff frequency from the velocity.
featuresize = 2 * data.x.mean() * vel / constants.c.cgs.value # vel MUST be given in units of cm
dlam = data.x[1] - data.x[0] # data.x MUST have constant x-spacing
Npix = featuresize / dlam
nsamples = data.size()
sample_rate = 1.0 / dlam
nyq_rate = sample_rate / 2.0 # The Nyquist rate of the signal.
width /= nyq_rate
cutoff_hz = min(1.0 / featuresize, nyq_rate - width * nyq_rate / 2.0) # Cutoff frequency of the filter
# The desired attenuation in the stop band, in dB.
ripple_db = 60.0
# Compute the order and Kaiser parameter for the FIR filter.
N, beta = kaiserord(ripple_db, width)
if N % 2 == 0:
N += 1
# Use firwin with a Kaiser window to create a lowpass FIR filter.
taps = firwin(N, cutoff_hz / nyq_rate, window=('kaiser', beta), pass_zero=False)
# Extend data to prevent edge effects
y = np.r_[data.y[::-1], data.y, data.y[::-1]]
# Use lfilter to filter data with the FIR filter.
smoothed_y = lfilter(taps, 1.0, y)
# The phase delay of the filtered signal.
delay = 0.5 * (N - 1) / sample_rate
delay_idx = np.searchsorted(data.x, data.x[0] + delay)
smoothed_y = smoothed_y[data.size() + delay_idx:-data.size() + delay_idx]
if linearize:
fcn = spline(data.x, smoothed_y)
return fcn(original_data.x)
else:
return smoothed_y
def ReadFits(datafile, errors=False, extensions=False, x=None, y=None, cont=None, return_aps=False, debug=False):
"""
Read a fits file. If extensions=False, it assumes IRAF's multispec format.
Otherwise, it assumes the file consists of several fits extensions with
binary tables, with the table names given by the x,y,cont, and errors keywords.
See ReadExtensionFits for a convenience function that assumes my standard names
Parameters:
===========
- datafile: string
The name of the file to read
- errors: boolean, integer, or string
If False, indicates there are no errors in the datafile
If an integer AND extensions = False, indicates the index
that the errors are found in.
If a string AND extenstions = True, indicates the name
of the error field in the binary table.
- extensions: boolean
Is the data stored in several fits extensions? If not,
we assume it is in multispec format
- x: string
The name of the field with the x-coordinate (wavelength, etc).
Ignored if extensions = False
- y: string
The name of the field with the y-coordinate (flux, etc).
Ignored if extensions = False
- cont: string
The name of the field with the continuum estimate.
Ignored if extensions = False
- return_aps: boolean
Return the aperture wavelength fields as well as the
extracted orders. The wavelength fields define the
wavelengths in multispec format. Ignored if extensions = True.
- debug: boolean
Print some extra information to screen
Returns:
========
A list of kglib.utils.DataStructures.xypoint instances with the data for each
echelle order.
"""
if debug:
print( "Reading in file %s: " % datafile)
if extensions:
# This means the data is in fits extensions, with one order per extension
# At least x and y should be given (and should be strings to identify the field in the table record array)
if type(x) != str:
x = raw_input("Give name of the field which contains the x array: ")
if type(y) != str:
y = raw_input("Give name of the field which contains the y array: ")
orders = []
hdulist = pyfits.open(datafile)
if cont == None:
if not errors:
for i in range(1, len(hdulist)):
data = hdulist[i].data
xypt = DataStructures.xypoint(x=data.field(x), y=data.field(y))
orders.append(xypt)
else:
if type(errors) != str:
errors = raw_input("Give name of the field which contains the errors/sigma array: ")
for i in range(1, len(hdulist)):
data = hdulist[i].data
xypt = DataStructures.xypoint(x=data.field(x), y=data.field(y), err=data.field(errors))
orders.append(xypt)
elif type(cont) == str:
if not errors:
for i in range(1, len(hdulist)):
data = hdulist[i].data
xypt = DataStructures.xypoint(x=data.field(x), y=data.field(y), cont=data.field(cont))
orders.append(xypt)
else:
if type(errors) != str:
errors = raw_input("Give name of the field which contains the errors/sigma array: ")
for i in range(1, len(hdulist)):
data = hdulist[i].data
xypt = DataStructures.xypoint(x=data.field(x), y=data.field(y), cont=data.field(cont),
err=data.field(errors))
orders.append(xypt)
else:
# Data is in multispec format rather than in fits extensions
# Call Rick White's script
try:
retdict = multispec.readmultispec(datafile, quiet=not debug)
except ValueError:
warnings.warn("Wavelength not found in file %s. Using a pixel grid instead!" % datafile)
hdulist = pyfits.open(datafile)
data = hdulist[0].data
hdulist.close()
numpixels = data.shape[-1]
numorders = data.shape[-2]
wave = np.array([np.arange(numpixels) for i in range(numorders)])
retdict = {'flux': data,
'wavelen': wave,
'wavefields': np.zeros(data.shape)}
# Check if wavelength units are in angstroms (common, but I like nm)
hdulist = pyfits.open(datafile)
header = hdulist[0].header
hdulist.close()
wave_factor = 1.0 #factor to multiply wavelengths by to get them in nanometers
for key in sorted(header.keys()):
if "WAT1" in key:
if "label=Wavelength" in header[key] and "units" in header[key]:
waveunits = header[key].split("units=")[-1]
if waveunits == "angstroms" or waveunits == "Angstroms":
# wave_factor = u.nm/u.angstrom
wave_factor = u.angstrom.to(u.nm)
if debug:
print( "Wavelength units are Angstroms. Scaling wavelength by ", wave_factor)
if errors == False:
numorders = retdict['flux'].shape[0]
else:
numorders = retdict['flux'].shape[1]
orders = []
for i in range(numorders):
wave = retdict['wavelen'][i] * wave_factor
if errors == False:
flux = retdict['flux'][i]
err = np.ones(flux.size) * 1e9
err[flux > 0] = np.sqrt(flux[flux > 0])
else:
if type(errors) != int:
errors = int(raw_input("Enter the band number (in C-numbering) of the error/sigma band: "))
flux = retdict['flux'][0][i]
err = retdict['flux'][errors][i]
cont = FittingUtilities.Continuum(wave, flux, lowreject=2, highreject=4)
orders.append(DataStructures.xypoint(x=wave, y=flux, err=err, cont=cont))
if return_aps:
# Return the aperture wavefields too
orders = [orders, retdict['wavefields']]
return orders
def plot_expected(orders, prim_spt, Tsec, instrument, vsini=None, rv=0.0, twoaxes=False):
"""
Plot the data orders, with a model spectrum added at appropriate flux ratio
Parameters
==========
- orders: A list of kglib.utils.Datastructures.xypoint instances
The observed spectra, split into echelle orders
- prim_spt: string
The primary star spectral type
- Tsec: float
The secondary temperature
- instrument: string
The name of the instrument the observation came from
- vsini: float
The vsini of the companion, in km/s
- rv: float
The rv shift of the companion
"""
sns.set_context("paper", font_scale=2.0)
sns.set_style("white")
sns.set_style("ticks")
# First, get the model
dir_prefix = "/media/ExtraSpace"
if not os.path.exists(dir_prefix):
dir_prefix = "/Volumes/DATADRIVE"
inst2hdf5 = {
"TS23": "{}/PhoenixGrid/TS23_Grid.hdf5".format(dir_prefix),
"HRS": "{}/PhoenixGrid/HRS_Grid.hdf5".format(dir_prefix),
"CHIRON": "{}/PhoenixGrid/CHIRON_Grid.hdf5".format(dir_prefix),
"IGRINS": "{}/PhoenixGrid/IGRINS_Grid.hdf5".format(dir_prefix),
}
hdf5_int = StellarModel.HDF5Interface(inst2hdf5[instrument])
wl = hdf5_int.wl
pars = {"temp": Tsec, "logg": 4.5, "Z": 0.0, "alpha": 0.0}
fl = hdf5_int.load_flux(pars)
# Broaden, if requested
if vsini is not None:
m = DataStructures.xypoint(x=wl, y=fl)
m = Broaden.RotBroad(m, vsini * units.km.to(units.cm))
wl, fl = m.x, m.y
# get model continuum
c = FittingUtilities.Continuum(wl, fl, fitorder=5, lowreject=2, highreject=10)
# Interpolate the model
x = wl * units.angstrom
plt.plot(wl, fl)
plt.plot(wl, c)
plt.show()
modelfcn = interp(x.to(units.nm), fl / c)
# Get the wavelength-specific flux ratio between the primary and secondary star
MS = SpectralTypeRelations.MainSequence()
Tprim = MS.Interpolate("temperature", prim_spt)
Rprim = MS.Interpolate("radius", prim_spt)
sec_spt = MS.GetSpectralType("temperature", Tsec, prec=1e-3)
Rsec = MS.Interpolate("radius", sec_spt)
flux_ratio = blackbody_lambda(x, Tprim) / blackbody_lambda(x, Tsec) * (Rprim / Rsec) ** 2
fluxratio_fcn = interp(x.to(units.nm), 1.0 / flux_ratio)
# Loop over the orders:
if twoaxes:
fig, axes = plt.subplots(2, 1, sharex=True)
top, bottom = axes
for order in orders:
order.cont = FittingUtilities.Continuum(order.x, order.y, fitorder=3, lowreject=2, highreject=5)
top.plot(order.x, order.y, "k-", alpha=0.4)
top.plot(order.x, order.cont, "r--")
total = order.copy()
xarr = total.x * (1 + rv / constants.c.to(units.km / units.s).value)
model = (modelfcn(xarr) - 1.0) * fluxratio_fcn(xarr)
total.y += total.cont * model
top.plot(total.x, total.y, "g-", alpha=0.4)
bottom.plot(total.x, total.y - order.y, "k-", alpha=0.4)
return fig, [top, bottom], orders
fig, ax = plt.subplots(1, 1)
for order in orders:
order.cont = FittingUtilities.Continuum(order.x, order.y, fitorder=3, lowreject=2, highreject=5)
ax.plot(order.x, order.y, "k-", alpha=0.4)
total = order.copy()
xarr = total.x * (1 + rv / constants.c.to(units.km / units.s).value)
model = (modelfcn(xarr) - 1.0) * fluxratio_fcn(xarr)
total.y += total.cont * model
ax.plot(total.x, total.y, "g-", alpha=0.4)
# Label
ax.set_xlabel("Wavelength (nm)")
ax.set_ylabel("Flux (arbitrary units)")
xlim = ax.get_xlim()
ylim = ax.get_ylim()
ax.plot([9e9], [9e9], "k-", label="Actual data")
ax.plot([9e9], [9e9], "g-", label="Expected data")
ax.set_xlim(xlim)
ax.set_ylim(ylim)
leg = ax.legend(loc="best", fancybox=True)
return fig, ax, orders
def MakeModelDicts(model_list, vsini_values=[10, 20, 30, 40], type='phoenix',
vac2air=True, logspace=False, hdf5_file=HDF5_FILE, get_T_sens=False):
"""
This will take a list of models, and output two dictionaries that are
used by GenericSearch.py and Sensitivity.py
Parameters:
===========
- model_list: iterable
A list of model filenames
- vsini_values: iterable
A list of vsini values to broaden
the spectrum by (we do that later!)
- type: string
The type of models. Currently,
phoenix, kurucz, and hdf5 are implemented
- vac2air: boolean
If true, assumes the model is in
vacuum wavelengths and converts to air
- logspace: boolean
If true, it will rebin the
data to a constant log-spacing
- hdf5_file: string
The absolute path to the HDF5 file
with the models. Only used if type=hdf5
- get_T_sens: boolean
Flag for getting the temperature sensitivity.
If true, it finds the derivative of each pixel dF/dT
Returns:
========
A dictionary containing the model with keys of temperature, gravity,
metallicity, and vsini,and another one with a processed flag with the same keys
"""
vsini_values = np.atleast_1d(vsini_values)
if type.lower() == 'phoenix':
modeldict = defaultdict(lambda: defaultdict(lambda: defaultdict(lambda: defaultdict(DataStructures.xypoint))))
processed = defaultdict(lambda: defaultdict(lambda: defaultdict(lambda: defaultdict(bool))))
for fname in model_list:
temp, gravity, metallicity = ClassifyModel(fname)
print("Reading in file %s" % fname)
data = pandas.read_csv(fname,
header=None,
names=["wave", "flux"],
usecols=(0, 1),
sep=' ',
skipinitialspace=True)
x, y = data['wave'].values, data['flux'].values
if vac2air:
n = 1.0 + 2.735182e-4 + 131.4182 / x ** 2 + 2.76249e8 / x ** 4
x /= n
model = DataStructures.xypoint(x=x * units.angstrom.to(units.nm), y=10 ** y)
if logspace:
xgrid = np.logspace(np.log(model.x[0]), np.log(model.x[-1]), model.size(), base=np.e)
model = FittingUtilities.RebinData(model, xgrid)
for vsini in vsini_values:
modeldict[temp][gravity][metallicity][vsini] = model
processed[temp][gravity][metallicity][vsini] = False
elif type.lower() == 'kurucz':
modeldict = defaultdict(
lambda: defaultdict(lambda: defaultdict(lambda: defaultdict(lambda: defaultdict(DataStructures.xypoint)))))
processed = defaultdict(
lambda: defaultdict(lambda: defaultdict(lambda: defaultdict(lambda: defaultdict(bool)))))
for fname in model_list:
temp, gravity, metallicity, a = ClassifyModel(fname)
print("Reading in file %s" % fname)
data = pandas.read_csv(fname,
header=None,
names=["wave", "flux"],
usecols=(0, 1),
sep=' ',
skipinitialspace=True)
x, y = data['wave'].values, data['flux'].values
if vac2air:
n = 1.0 + 2.735182e-4 + 131.4182 / x ** 2 + 2.76249e8 / x ** 4
x /= n
model = DataStructures.xypoint(x=x * units.angstrom.to(units.nm), y=10 ** y)
if logspace:
xgrid = np.logspace(np.log(model.x[0]), np.log(model.x[-1]), model.size(), base=np.e)
model = FittingUtilities.RebinData(model, xgrid)
for vsini in vsini_values:
modeldict[temp][gravity][metallicity][a][vsini] = model
processed[temp][gravity][metallicity][a][vsini] = False
elif type.lower() == 'hdf5':
hdf5_int = HDF5Interface(hdf5_file)
x = hdf5_int.wl
wave_hdr = hdf5_int.wl_header
if vac2air:
if not wave_hdr['air']:
n = 1.0 + 2.735182e-4 + 131.4182 / x ** 2 + 2.76249e8 / x ** 4
x /= n
elif wave_hdr['air']:
raise GridError(
'HDF5 grid is in air wavelengths, but you requested vacuum wavelengths. You need a new grid!')
modeldict = defaultdict(
lambda: defaultdict(lambda: defaultdict(lambda: defaultdict(lambda: defaultdict(DataStructures.xypoint)))))
processed = defaultdict(
lambda: defaultdict(lambda: defaultdict(lambda: defaultdict(lambda: defaultdict(bool)))))
for pars in model_list:
temp, gravity, metallicity, a = pars['temp'], pars['logg'], pars['Z'], pars['alpha']
y = hdf5_int.load_flux(pars)
model = DataStructures.xypoint(x=x * units.angstrom.to(units.nm), y=y)
for vsini in vsini_values:
modeldict[temp][gravity][metallicity][a][vsini] = model
processed[temp][gravity][metallicity][a][vsini] = False
else:
raise NotImplementedError("Sorry, the model type ({:s}) is not available!".format(type))
if get_T_sens:
# Get the temperature sensitivity. Warning! This assumes the wavelength grid is the same in all models.
sensitivity = defaultdict(
lambda: defaultdict(lambda: defaultdict(lambda: defaultdict(lambda: defaultdict(DataStructures.xypoint)))))
Tvals = sorted(modeldict.keys())
for i, T in enumerate(Tvals):
gvals = sorted(modeldict[T].keys())
for gravity in gvals:
metal_vals = sorted(modeldict[T][gravity].keys())
for metal in metal_vals:
alpha_vals = sorted(modeldict[T][gravity][metal].keys())
for alpha in alpha_vals:
# get the temperature just under this one
lower, l_idx = get_model(modeldict, Tvals, i, gravity, metal, vsini_values[0], alpha, mode='lower')
upper, u_idx = get_model(modeldict, Tvals, i, gravity, metal, vsini_values[0], alpha, mode='upper')
T_low = Tvals[l_idx]
T_high = Tvals[u_idx]
slope = (upper.y - lower.y) / (T_high - T_low)
for vsini in vsini_values:
sensitivity[T][gravity][metal][alpha][vsini] = slope**2
return modeldict, processed, sensitivity
return modeldict, processed
def Correlate(data, model_orders, debug=False, addmode="ML",
orderweights=None, get_weights=False, prim_teff=10000.0):
"""
This function does the actual correlation. The interface is slightly less useful than GetCCF,
but can still be called by the user.
Parameters:
===========
- data: list of kglib.utils.DataStructures.xypoint instances
The data we are cross-correlating against. Each element in the list
is treated like an echelle order.
- model_orders: list of kglib.utils.DataStructures.xypoint instances
Models relevant for each data orders. Must have the same
length as data
- debug: boolean
Prints debugging info to the screen, and saves various files.
- addmode: string
The CCF addition mode. The default is Maximum Likelihood
(from Zucker 2003, MNRAS, 342, 1291). The other valid options
are "simple", which will just do a straight addition,
"dc", which weights by the CCF value itself, and "weighted",
which weights each order. Maximum Likelihood is better for
finding weak signals, but simple is better for determining
parameters from the CCF (such as vsini)
- orderweights: list of floats
Weights to apply to each order. Only used if addmode="weighted".
Must have the same length as the data list
- get_weights: boolean
If true, attempts to determine weights from the information content
and flux ratio of the companion spectra.
The weights are only used if addmode="weighted"
- prim_teff: float
The effective temperature of the primary star. Used to determine the
flux ratio, which in turn is used to make the weights. Ignored if
addmode is not "weighted" or get_weights is False.
Returns:
========
A CCFContainer object
"""
# Error checking
if "weighted" in addmode.lower() and orderweights is None and not get_weights:
raise ValueError("Must give orderweights if addmode == weighted")
corrlist = []
normalization = 0.0
info_content = []
flux_ratio = []
snr = []
for ordernum, order in enumerate(data):
model = model_orders[ordernum]
if get_weights:
slopes = [(model.y[i + 1] / model.cont[i + 1] - model.y[i - 1] / model.cont[i - 1]) /
(model.x[i + 1] - model.x[i - 1]) for i in range(1, model.size() - 1)]
prim_flux = Planck(model.x * units.nm.to(units.cm), prim_teff)
lines = FittingUtilities.FindLines(model)
sec_flux = np.median(model.y.max() - model.y[lines])
flux_ratio.append(np.median(sec_flux) / np.median(prim_flux))
info_content.append(np.sum(np.array(slopes) ** 2))
snr.append(1.0 / np.std(order.y))
reduceddata = order.y / order.cont
reducedmodel = model.y / model.cont
# Get the CCF for this order
l = np.searchsorted(model.x, order.x[0])
if l > 0:
if order.x[0] >= model.x[l]:
dl = (order.x[0] - model.x[l]) / (model.x[l + 1] - model.x[l])
l += dl
else:
logging.debug('Less!')
dl = (model.x[l] - order.x[0]) / (model.x[l] - model.x[l - 1])
l -= dl
logging.debug('dl = {}'.format(dl))
ycorr = Normalized_Xcorr.norm_xcorr(reduceddata, reducedmodel, trim=False)
N = ycorr.size
distancePerLag = np.log(model.x[1] / model.x[0])
v1 = -(order.size() + l - 0.5) * distancePerLag
vf = v1 + N * distancePerLag
offsets = np.linspace(v1, vf, N)
velocity = -offsets * constants.c.cgs.value * units.cm.to(units.km)
corr = DataStructures.xypoint(velocity.size)
corr.x = velocity[::-1]
corr.y = ycorr[::-1]
# Only save part of the correlation
left = np.searchsorted(corr.x, minvel)
right = np.searchsorted(corr.x, maxvel)
corr = corr[left:right]
# Make sure that no elements of corr.y are > 1!
if max(corr.y) > 1.0:
corr.y /= max(corr.y)
# Save correlation
if np.any(np.isnan(corr.y)):
warnings.warn("NaNs found in correlation from order %i\n" % (ordernum + 1))
continue
normalization += float(order.size())
corrlist.append(corr.copy())
if get_weights:
if debug:
print("Weight components: ")
print("lam_0 info flux ratio, S/N")
for i, f, o, s in zip(info_content, flux_ratio, data, snr):
print(np.median(o.x), i, f, s)
info_content = (np.array(info_content) - min(info_content)) / (max(info_content) - min(info_content))
flux_ratio = (np.array(flux_ratio) - min(flux_ratio)) / (max(flux_ratio) - min(flux_ratio))
snr = (np.array(snr) - min(snr)) / (max(snr) - min(snr))
orderweights = (1.0 * info_content ** 2 + 1.0 * flux_ratio ** 2 + 1.0 * snr ** 2)
orderweights /= orderweights.sum()
logging.debug('Weights:')
logging.debug(orderweights)
# Add up the individual CCFs
total = corrlist[0].copy()
total_ccfs = CCFContainer(total.x)
if addmode.lower() == "ml" or addmode.lower() == 'all':
# use the Maximum Likelihood method from Zucker 2003, MNRAS, 342, 1291
total.y = np.ones(total.size())
for i, corr in enumerate(corrlist):
correlation = spline(corr.x, corr.y, k=1)
N = data[i].size()
total.y *= np.power(1.0 - correlation(total.x) ** 2, float(N) / normalization)
total_ccfs['ml'] = np.sqrt(1.0 - total.y)
if addmode.lower() == "simple" or addmode.lower() == 'all':
# do a simple addition
total.y = np.zeros(total.size())
for i, corr in enumerate(corrlist):
correlation = spline(corr.x, corr.y, k=1)
total.y += correlation(total.x)
total_ccfs['simple'] = total.y / float(len(corrlist))
if addmode.lower() == "dc" or addmode.lower() == 'all':
total.y = np.zeros(total.size())
for i, corr in enumerate(corrlist):
N = data[i].size()
correlation = spline(corr.x, corr.y, k=1)
total.y += float(N) * correlation(total.x) ** 2 / normalization
total_ccfs['dc'] = np.sqrt(total.y)
if addmode.lower() == "weighted" or (addmode.lower() == 'all' and orderweights is not None):
total.y = np.zeros(total.size())
for i, corr in enumerate(corrlist):
w = orderweights[i] / np.sum(orderweights)
correlation = spline(corr.x, corr.y, k=1)
total.y += w * correlation(total.x) ** 2
total_ccfs['weighted'] = np.sqrt(total.y)
if addmode.lower() == 'simple-weighted' or (addmode.lower() == 'all' and orderweights is not None):
total.y = np.zeros(total.size())
for i, corr in enumerate(corrlist):
w = orderweights[i] / np.sum(orderweights)
correlation = spline(corr.x, corr.y, k=1)
total.y += correlation(total.x) * w
total_ccfs['simple-weighted'] = total.y / float(len(corrlist))
if addmode.lower() == 'all':
return (total_ccfs, corrlist) if debug else total_ccfs
return (total_ccfs[addmode], corrlist) if debug else total_ccfs[addmode]
def Process(model, data, vsini, resolution, debug=False):
"""
Process the model to prepare for cross-correlation.
Parameters:
===========
- data: list of kglib.utils.DataStructures.xypoint instances
The data we are cross-correlating against. Each element in the list
is treated like an echelle order.
- vsini: float
The rotational velocity for the model template, in km/s
- resolution: float
The detector resolution. The model is convolved with a gaussian of appropriate width to get
to this resolution.
- debug: boolean
Print a bit more information and output the broadened model to './Test_model.dat'
Returns:
=========
- model_orders: list of kglib.utils.DataStructures.xypoint instances
The broadened models, resampled to the same spacing as the data and ready for cross-correlation.
"""
# Read in the model if necessary
if isinstance(model, str):
logging.debug("Reading in the input model from {0:s}".format(model))
x, y = np.loadtxt(model, usecols=(0, 1), unpack=True)
x = x * units.angstrom.to(units.nm)
y = 10 ** y
left = np.searchsorted(x, data[0].x[0] - 10)
right = np.searchsorted(x, data[-1].x[-1] + 10)
model = DataStructures.xypoint(x=x[left:right], y=y[left:right])
elif not isinstance(model, DataStructures.xypoint):
raise TypeError(
"Input model is of an unknown type! Must be a DataStructures.xypoint or a string with the filename.")
# Linearize the x-axis of the model
logging.debug('Linearizing model')
xgrid = np.linspace(model.x[0], model.x[-1], model.size())
model = FittingUtilities.RebinData(model, xgrid)
# Broaden
logging.debug("Rotationally broadening model to vsini = {0:g} km/s".format(vsini * units.cm.to(units.km)))
if vsini > 1.0 * units.km.to(units.cm):
model = RotBroad.Broaden(model, vsini, linear=True)
# Reduce resolution
logging.debug(u"Convolving to the detector resolution of {}".format(resolution))
if resolution is not None and 5000 < resolution < 500000:
model = FittingUtilities.ReduceResolution(model, resolution)
# Rebin subsets of the model to the same spacing as the data
model_orders = []
if debug:
model.output("Test_model.dat")
for i, order in enumerate(data):
if debug:
sys.stdout.write("\rGenerating model subset for order %i in the input data" % (i + 1))
sys.stdout.flush()
# Find how much to extend the model so that we can get maxvel range.
dlambda = order.x[order.size() / 2] * maxvel * 1.5 / 3e5
left = np.searchsorted(model.x, order.x[0] - dlambda)
right = np.searchsorted(model.x, order.x[-1] + dlambda)
right = min(right, model.size() - 2)
# Figure out the log-spacing of the data
logspacing = np.log(order.x[1] / order.x[0])
# Finally, space the model segment with the same log-spacing
start = np.log(model.x[left])
end = np.log(model.x[right])
xgrid = np.exp(np.arange(start, end + logspacing, logspacing))
segment = FittingUtilities.RebinData(model[left:right + 1].copy(), xgrid)
segment.cont = FittingUtilities.Continuum(segment.x, segment.y, lowreject=1.5, highreject=5, fitorder=2)
model_orders.append(segment)
return model_orders
