Reference / API

Model & Components

Model(source[, effects, effect_names, …]) An observer-frame model, composed of a Source and zero or more effects.

Source component of Model

Source() An abstract base class for transient models.
TimeSeriesSource(phase, wave, flux[, …]) A single-component spectral time series model.
StretchSource(phase, wave, flux[, name, version]) A single-component spectral time series model, that “stretches” in time.
SALT2Source([modeldir, m0file, m1file, …]) The SALT2 Type Ia supernova spectral timeseries model.

Effect components of Model: interstellar dust extinction

PropagationEffect Abstract base class for propagation effects.
CCM89Dust() Cardelli, Clayton, Mathis (1989) extinction model dust.
OD94Dust() O’Donnell (1994) extinction model dust.
F99Dust([r_v]) Fitzpatrick (1999) extinction model dust with fixed R_V.

Bandpass & Magnitude Systems

Bandpass(wave, trans[, wave_unit, …]) Transmission as a function of spectral wavelength.
AggregateBandpass(transmissions[, …]) Bandpass defined by multiple transmissions in series.
BandpassInterpolator(transmissions, …[, …]) Bandpass generator defined as a function of focal plane position.
MagSystem([name]) An abstract base class for magnitude systems.
ABMagSystem([name]) Magnitude system where a source with F_nu = 3631 Jansky at all frequencies has magnitude 0 in all bands.
SpectralMagSystem(refspectrum[, name]) A magnitude system defined by a fundamental spectrophotometric standard.
CompositeMagSystem([bands, families, name]) A magnitude system defined in a specific set of bands.


Functions for reading and writing photometric data, gridded data, extinction maps, and more.

read_lc(file_or_dir[, format]) Read light curve data for a single supernova.
write_lc(data, fname[, format]) Write light curve data.
read_bandpass(fname[, fmt, wave_unit, …]) Read bandpass from two-column ASCII file containing wavelength and transmission in each line.
load_example_data() Load an example photometric data table.
read_snana_ascii(fname[, default_tablename]) Read an SNANA-format ascii file.
read_snana_fits(head_file, phot_file[, snids, n]) Read the SNANA FITS format: two FITS files jointly representing metadata and photometry for a set of SNe.
read_snana_simlib(fname) Read an SNANA ‘simlib’ (simulation library) ascii file.
read_griddata_ascii(name_or_obj) Read 2-d grid data from a text file.
read_griddata_fits(name_or_obj[, ext]) Read a multi-dimensional grid of data from a FITS file, where the grid coordinates are encoded in the FITS-WCS header keywords.
write_griddata_ascii(x0, x1, y, name_or_obj) Write 2-d grid data to a text file.
write_griddata_fits(x0, x1, y, name_or_obj) Write a 2-d grid of data to a FITS file

Fitting Photometric Data

Estimate model parameters from photometric data

fit_lc(data, model, vparam_names[, bounds, …]) Fit model parameters to data by minimizing chi^2.
mcmc_lc(data, model, vparam_names[, bounds, …]) Run an MCMC chain to get model parameter samples.
nest_lc(data, model, vparam_names, bounds[, …]) Run nested sampling algorithm to estimate model parameters and evidence.

Convenience functions

select_data(data, index) Convenience function for indexing photometric data with covariance.
chisq(data, model[, modelcov]) Calculate chisq statistic for the model, given the data.
flatten_result(res) Turn a result from fit_lc into a simple dictionary of key, value pairs.


Convenience functions for quick standard plots (requires matplotlib)

plot_lc([data, model, bands, zp, zpsys, …]) Plot light curve data or model light curves.


zdist(zmin, zmax[, time, area, ratefunc, …]) Generate a distribution of redshifts.
realize_lcs(observations, model, params[, …]) Realize data for a set of SNe given a set of observations.


Register and retrieve custom built-in sources, bandpasses, and magnitude systems

register(instance[, name, data_class, force]) Register a class instance.
register_loader(data_class, name, func[, …]) Register a data reading function.
get_source(name[, version, copy]) Retrieve a Source from the registry by name.
get_bandpass(name, \*args) Get a Bandpass from the registry by name.
get_magsystem(name) Get a MagSystem from the registry by name.

Class Inheritance Diagrams

Inheritance diagram of Source, TimeSeriesSource, StretchSource, SALT2Source
Inheritance diagram of PropagationEffect, F99Dust, OD94Dust, CCM89Dust
Inheritance diagram of MagSystem, ABMagSystem, SpectralMagSystem