TransitModelFit#

class stellarphot.transit_fitting.TransitModelFit[source]#

Bases: object

Transit model fits to observed light curves.

Parameters:

batman_paramsbatman.TransitParams: Parameters for the batman transit model. If not provided, the default parameters will be used.

Attributes:

BICfloat: Bayesian Information Criterion for the fit. This is calculated after the fit is performed.
n_fit_parametersint: Number of parameters that were fit. This is calculated after the fit is performed.
widtharray-like: weights : array-like

Attributes Summary

`BIC`
`airmass`	airmass : array-like
`data`	data : array-like
`model`	model : `astropy.modeling.Model`
`n_fit_parameters`
`spp`	spp : array-like
`times`	times : array-like
`width`	weights : array-like

Methods Summary

`data_light_curve`([data, detrend_by])	Function to return data light curve, optionally detrended by one or more parameters.
`fit`()	Perform a fit and update the model with best-fit values.
`model_light_curve`([at_times, detrend_by])	Calculate the light curve corresponding to the model, optionally detrended by one or more parameters.
`setup_model`([binned_data, t0, depth, ...])	Configure a transit model for fitting.

Attributes Documentation

BIC#

airmass#

airmassarray-like: Airmass at each time. Must be set before fitting.

data#

dataarray-like: Observed fluxes. Must be set before fitting.

model#

modelastropy.modeling.Model: The model used for fitting. This is a combination of the batman transit model and any other trends that are included in the fit. This is set up when the setup_model method is called.

n_fit_parameters#

spp#

spparray-like: Sky per pixel at each time. Must be set before fitting.

times#

timesarray-like: Times at which the light curve is observed. Must be set before fitting.

width#

weightsarray-like: Weights to use for fitting. If not provided, all weights are set to 1.

Methods Documentation

data_light_curve(data=None, detrend_by=None)[source]#

Function to return data light curve, optionally detrended by one or more parameters.

Parameters:

dataarray-like, optional: Data to use for calculating the light curve. If not provided, the data used for fitting will be used.
detrend_bystr or list of str: Parameter(s) to detrend by. If None, no detrending is done. If 'all', all parameters that are set will be used for detrending.

Returns:

dataarray-like: Data light curve, detrended if requested.

fit()[source]#: Perform a fit and update the model with best-fit values.

model_light_curve(at_times=None, detrend_by=None)[source]#

Calculate the light curve corresponding to the model, optionally detrended by one or more parameters.

Parameters:

at_timesarray-like: Times at which to calculate the model. If not provided, the times used for fitting will be used.
detrend_bystr or list of str: Parameter(s) to detrend by. If None, no detrending is done. If 'all', all parameters that are set will be used for detrending.

Returns:

modelarray-like: Model light curve.

setup_model(binned_data=None, t0=0, depth=0, duration=0, period=1, inclination=90, airmass_trend=0.0, width_trend=0.0, spp_trend=0.0, model_options=None)[source]#

Configure a transit model for fitting. The duration and depth are used to estimate underlying fit parameters; they are not themselves fit parameters.

Parameters:

t0float: Time of the center of the transit. Can be in any units but should be consistent with the units for the period and for the times used for fitting.
depthfloat: Depth of the transit in parts per thousand.
durationfloat: Duration of the transit,in the same units as t0 and period.
periodfloat: Period of the planet. Should be in the same units as t0 and times used for fitting.
inclinationfloat: Inclination of the orbit, in degrees.
airmass_trendfloat, optional: Coefficient for a linear trend in airmass.
width_trendfloat: Coefficient for a linear trend in stellar width.
spp_trendfloat: Coefficient for a linear trend in sky per pixel.
optionsTransitModelOptions, optional: Options for the transit model fit.

Returns:

None: Sets values for the model parameters.